/HAM/ Amateur, CB, Shortwave Listening, Pirate Radio, Kerchunking General

[Anonymous No.2564229]

Surprise SSTV edition

Old thread got kerchunked and taken off air: >>2545217

Eternal thread theme: https://www.youtube.com/watch?v=7gd43b_ZcuU

>New to /ham/? Read this shit!
http://www.arrl.org/what-is-ham-radio
https://www.fcc.gov/wireless/bureau-divisions/mobility-division/amateur-radio-service
>Your search engine of choice works well too!

The FAQ is now back:
https://wiki.cybsec.io/index.php/HamFAQ
>NEW FAQ is updated to preview 13
https://files.catbox.moe/3xr6gh.htm
>I can only find Preview 13 prepackaged with some other documents:
https://files.catbox.moe/4ghken.zip
>The wiki is down but is archived: https://archive.is/PjR5s
>Idiot's Guide to Coax Cable
https://www.pcs-electronics.com/guide_coax.php
>Looking for frequencies to monitor near you?
http://www.radioreference.com
>Basic Rx loop fundamentals
https://www.w8ji.com/magnetic_receiving_loops.htm
>DIY SWL Mag. Loop
http://www.kr1st.com/swlloop.htm
>Small Tx Loop
http://webclass.org/k5ijb/antennas/Small-magnetic-loops.htm
>In Depth Loop articles
http://www.kk5jy.net/magloop/
>Homebrew RF Circuits
https://www.qsl.net/va3iul/Homebrew_RF_Circuit_Design_Ideas/Homebrew_RF_Circuit_Design_Ideas.htm
>NEW Library
https://mega.nz/file/UCgEGAjb#rwNcnMAQCUUbSp8supsFvn9QEHCWUW86eLcZa16ZG4Y

>Online Practice Tests:
http://aa9pw.com/
https://hamstudy.org/
https://hamexam.org/
> Real-Time Propagation Data
http://prop.kc2g.com/
>Space Weather
https://www.swpc.noaa.gov/communities/radio-communications
>WSJT-X 2.1 User Guide
https://physics.princeton.edu/pulsar/k1jt/wsjtx-doc/wsjtx-main-2.1.2.html
>Homosexual (ft8) guide
https://www.g4ifb.com/FT8_Hinson_tips_for_HF_DXers.pdf
>APRS
http://www.aprs.org/
>how do I into Morse code in a good way?
https://pastebin.com/HByjfN4F

[Anonymous No.2564243]

Guide me on these please.
I was searching for a 2.4ghz patch antenna that I can recreate on a pcb. I've found different designs, like these for example. How to figure out the differences and choose the best one?

[Anonymous No.2564245]

>>2564243
they will have ratings, usually.

big arrays like bottom-left are more directional, like a flashlight rather than a lamp. Bigger is almost always better in that sense, provided the design is still valid. Not sure what top-right is, the cable and connector look wrong.

[Anonymous No.2564247]

>>2564245
But look for the top left and bottom left for example. That leg is different. There's no cuts out at the leg, even though I found the dimensions. I'm pretty sure I HAVE to make it exactly like that, otherwise it won't work. So how does the array work without following these rules?

[Anonymous No.2564256]

The Chad repeater.

[Anonymous No.2564262]

>>2564229

[Anonymous No.2564344]

https://www.rtl-sdr.com/the-us-airforce-may-have-shot-down-an-amateur-radio-pico-balloon-over-canada/

[Anonymous No.2564345]

>>2564229
HAM!

[Anonymous No.2564355]

Believe it or not, but I just found a Tx/Rx 5.8 Ghz module for 2 bucks. Is it possible to modify it so I can receive signals on much longer distances?

[Anonymous No.2564372]

>>2564262
>truegrave09
How can one anon be so based?

[Anonymous No.2564447]

>>2564355
are these modules the ones used for dead angle detection in cars ? You know the "radar" used to signal if there's a car on the other lane where you can't see it ?

[Anonymous No.2564460]

>>2564447
No, those are specifically 77/79Ghz

[Anonymous No.2564473]

Cannot find an answer to my dumb question. If I put my random wire antenna vertical, will it be omnidirectional? I'd rather not have any null zones in the radiation pattern.

[Anonymous No.2564528]

>>2564473
That's the problem my man. The thread is about HAM and people here are good at choosing and buying expensive radio toys. But as soon as you want to do something yourself nobody is able to help. Not because they are necessarily assholes, but because they simply don't know themselves how antennas and rf hardware really work. General understanding is there, but it's mostly not enough to answer specific questions. Even though this is /diy, not /buy_offshelf_transmitters

[Anonymous No.2564533]

>>2564473
yes, it's a vertical antenna, widely used for HF
https://www.hamradio.me/antennas/answer-to-everything-43-feet-antenna.html
the angle of maximum radiation will vary but is lower than for a dipole at the adequate heigh (that is half wavelength)
a vertical dipole is interesting too (you run the feeder inside the lower half part of the antenna)

[Anonymous No.2564536]

>>2564473
>>2564533
and if it's end fed (bottom fed in this case ?) you might need radials,
a lot of them, half wave length, so for example you put 4 radials for 80m, 4 for 40m, 4 for 20m etc.

[Anonymous No.2564560]

Did anyone hear Bouvet?
They're already off the island.

[Anonymous No.2564606]

>>2564528
I mean.. Try even finding the parts at an electronic store to make a radio, everythings switched to PLLs. Try sourcing the aluminum for a vertical HF antenna, it's much cheaper to buy. Once you start talking microwave frequencies then PCB thickness, stray capacitance and dielectric constants become important.

HF is as easy as you can work with and it's still hard. As you go up in frequency the parts get smaller and the tools get more expensive.

[Anonymous No.2564615]

>>2564606
I could do a PBC array patch antenna for this >>2564355 by ordering a PCB from a Chinese manufacturer, no problem.
Can you give me RX antenna design that will work? How to understand if it's even possible?

[Anonymous No.2564713]

QRD on X-class xray flares? What cool radio stuff can I do with this baby?

[Anonymous No.2564737]

>>2564615
>I could do a PBC array patch antenna for this >>2564355 by ordering a PCB from a Chinese manufacturer, no problem.
Can you give me RX antenna design that will work? How to understand if it's even possib

What's wrong with its existing antennas? I could do a PBC array patch antenna for this >>2564355 by ordering a PCB from a Chinese manufacturer, no problem.
Can you give me RX antenna design that will work? How to understand if it's even possible

Bruh. It has antennas. What's wrong with them? If you don't already know that you can do better then you can't.

bla bla bla, SWR, insertion loss, antenna gain, antenna diversity. bla bla. You're just going to fuck it up if you try.

[Anonymous No.2564739]

>>2564615
>I could do a PBC array patch antenna for this >>2564355 by ordering a PCB from a Chinese manufacturer, no problem.
>Can you give me RX antenna design that will work? How to understand if it's even possible?

Bruh. It has antennas. What's wrong with them? If you don't already know that you can do better then you can't.

bla bla bla, SWR, insertion loss, antenna gain, antenna diversity. bla bla. You're just going to fuck it up if you try.

[Anonymous No.2564742]

>>2564713
You can annoy the hell out of that mexico city taxi dispatch center that uses 27.165mhz. The lady speaking spanish with the really long roger beep.

[Anonymous No.2564754]

>>2564560
I heard them on 15 and 30m but never got through.

[Anonymous No.2564764]

>>2564737
>>2564739
Why am I going to fuck it up, if it's you (or another educated anon) who would give me the antenna design?

You have all info here - 5.8Ghz, patch array, I need higher gain to receive signals further away. What antenna design to use?

[Anonymous No.2564773]

>>2564764
Because you're taking something finely tuned, assuming you can do better and then asking to be spoonfed how to do better. You can't.

[Anonymous No.2564774]

>>2564773
What do you mean I can't? The antenna has to follow strict rules and be sized exactly. Give me the dimensions of each line and square and I replicate it easily on a PCB with accuracy of what JLCPCB is capable of, I guess 0.2mm. If you don't know how to do that, it's fine, no need to pretend and act big here.

[Anonymous No.2564838]

What is the best handheld I can buy to communicate in a city environment without license?

Inb4 baofeng

[Anonymous No.2564888]

>>2564533
>>2564536
Thanks for answering the question. I was hoping to avoid the need for radials and just put the one I already have up a tall tree since it works on most bands with mimimal matching even on 80m (the band I want to work the most along eith 40m). The long and many radials will be an issue due to space. I have to do a lot of bends as it is for my current random wire, and still get nullzones. But you pointed me in a direction for futher research. Thank you.

[Anonymous No.2564890]

>>2564754
It came and went so quick.
I work from home and dedicated too much time to monitoring what they were up to and nothing.
There's a Russian DX crew that doesn't mess around. When they hit a country, I'm certain I'll hit them on all bands.
Oh well, perhaps it's #2 for a reason.

[Anonymous No.2564918]

>>2564774
>develop my "not product" for free

[Anonymous No.2564988]

should I troll the repeaters

[Anonymous No.2565133]

>>2564890
I don't know how exactly, but a lot of things went wrong. Ended up using only fallback equipment and max 100W and ran out of food early.

[Anonymous No.2565317]

>give us money and your smart
Anyone else repulsed by Flex and their homo audience?

[Anonymous No.2565322]

>>2565133
I was following the site announcements on sites and it sounded like bad luck or bad planning, or a mix of both.
Oh well, sounds like it took a lot of resources and I appreciate the effort

[Anonymous No.2565422]

Don't give your money to the antenna jews so they can buy their third home in the Bahamas.

[Anonymous No.2565444]

>>2565422
I've been using a tuned dipole (I have a nanovna). So I get away with no tuner. People worry about getting the height perfect. I talked to Europe with an inverted V and 20 watts. With 100 watts/ 10watts digital or Morse code you can reach the world.
With a dipole, nanovna, voacap and 75 watts I've worked the whole world. Step 1. Is get an antenna up. Using 75ohm tv coax only gives you a swr mismatch of 1.5. The dipole probably won't be 50 ohms so why worry about it? A swr of 2 is like .8db of loss? So what, and most rigs will work with a swr of two. Get antenna up. Get going. It is that easy. If you have an y problems anons will be glad to help! I'm responding to (you) but the content of this message isn't directed to you.

[Anonymous No.2565445]

>>2564606
Best time to be alive, just have to mail order. Dan's small parts and kits. Digikey. Mouser.

[Anonymous No.2565448]

>>2564473
How long is a piece of string in a snowstorm in Ohio? You will need to learn and play with eznac and model your ground and surrounding structures correctly.

[Anonymous No.2565862]

>>2565317
I find it rather nauseating. Anyway, which is the most advanced rig? FTDX-9000D?

[Anonymous No.2565921]

I would really like to make a small project for my RC submarine and make it truly wireless. I know for communication under the water I would need very low frequencies, but which ones?

[Anonymous No.2565962]

>>2565862
Or perhaps pic. related?

>>2565921
Subs use kHz frequencies, very low speed and not practical for your purposes. Since stealth is not important, you might use acoustics instead.

[Anonymous No.2565966]

>>2564229
anyone know how these work? I can't find any info but I would love to attach a 100W amplifier to Hulk Hogan

[Anonymous No.2565983]

>>2565966
>find out frequency
>find out power output
>get PA for frequency range
>seething boomers at this end of the story
Godspeed, anon.

[Anonymous No.2566020]

anyone here familiar with pirate fm radio

[Anonymous No.2566024]

>be new ham
>want into tube radio
>light filament of tube on improvised socket
>with borrowed transformer
Kneel before me.

[Anonymous No.2566155]

>>2565862
We've hit a spot of diminishing returns.
Nobody uses/know half of their radios features, and half of the features aren't needed if you feed the audio to your PC.
Ham needs open source PC software to progress, not overpriced hardware.

[Anonymous No.2566181]

I'm still sad that radioboard is dead

[Anonymous No.2566396]

>>2564262
Birb is not for sexual

[Anonymous No.2566405]

>>2565862
>implying this is somehow more useful that a frog 7
captcha: TTRTDX

[Anonymous No.2566446]

>>2566181
Any other good sites that could be added to the FAQ?

[Anonymous No.2566629]

>>2566155
I guess that is why 818nd was so popular.

[Anonymous No.2566646]

>>2566446
antiqueradios.com/forums/index.php
The antique radio forums are the closest thing around that still has some actual traffic

[Anonymous No.2566757]

I may not qualify as electronically illiterate, but it sure looks like it.

[Anonymous No.2566761]

>>2566757
that improvised tube socket is fuckin rad

[Anonymous No.2566766]

>>2566757
that's awesome anon

[Anonymous No.2566787]

>>2566757
Do you also consider a coffee can an adequate indoor fireplace?

[Anonymous No.2566797]

>>2566787
Why let it go to waste?

[Anonymous No.2566820]

>>2564229
which one of you faggots jams the sked on w2rn at 6 am every morning, i almost admire the autism. every single time ive ever tuned in since july, which has been most days, someone is squeaking into the mic and spamming slow scan over the two people that talk on their drive to work

[Anonymous No.2566956]

Let's say I have an RF generator, that feeds into coax. There is an impedance matching network between the generator and coax. The coax then feeds into an antenna (technically an RF coil).
Do I need to have a second impedance matching network at the output of the coax, into the RF coil?

[Anonymous No.2567040]

>>2566820
see >>2564262

[Anonymous No.2567042]

>>2564256
i always ask people why something like this wouldnt work. why does it not

[Anonymous No.2567104]

>>2566956
Yes, if the antenna isn't the same impedance as the coax.

[Anonymous No.2567122]

Recently had bad flooding, power cuts, internet cutting out, and cell-towers losing power after a cyclone went through. Thinking for the future from the perspective of the local council, what options are there for more bulletproof emergency communication systems? The important parts would be getting the technology in as many people's hands as possible, and to make it easy to use.

My mind is either going to cell-towers with an emergency SMS-only mode for power saving and a large battery backup supply, or to something like LoRaWAN nodes scattered about the place. But I'm wondering whether existing cell-phones would be better communication devices than a dedicated terminal that will run for weeks on AA batteries, since during the power-cuts people were really struggling to charge their cell phones, plus a lot of them aren't waterproof. Cell-towers being a single point of failure is also somewhat worrying.

Maybe some sort of CB repeater nodes?

[Anonymous No.2567126]

>>2567122
you need a lot of equipment just for SMS, the same as for calls, for 2G-3G networks : the antennas are connected to BSC-RNC then MSC (MGW for voice stream), HLR-HSS, STP, SMS center, SMS gateways (to provide access to other users for example to broadcast emergency SMS)
So the whole network. For 4G-5G, same but with IMS equipment instead of MSC and MGW and STP (picrel)
mobile phone networks don't function only with local antennas all the management is done in the core network.

[Anonymous No.2567135]

>>2567126
All the local equipment should be inside the existing cell-towers. But if those cell-towers are cut off from the wider internet, are you suggesting that they won't be able to function as a standalone network? Do cell-towers wirelessly communicate directly to other cell-towers?
It would also have to be carrier agnostic, which is likely an issue since I'm pretty sure each carrier has its own towers.

What if you go to 2G or 1G? Last I looked into it cell-towers or phones are backwards compatible to that, since a guy used an Hack-RF One as a pseudo cell-tower.

[Anonymous No.2567136]

>>2567040
I don't think a goose can use a radio.

[Anonymous No.2567137]

>>2567135
you can't put that kind of equipment in a cell-tower, cell-towers don't communicate directly to other cell-towers
It takes a lot of space and energy. There is no small scale version of it. Mobile phone networks are heavily centralized and energy hungry, they are not fit for disasters as if you lost one equipment they fail entirely, anyway most recent mobile phones have 48H max autonomy and people don't care about being independent for energy, not at least a bit to charge their mobile phones (that are also calculators, flashlights, notepads and cameras even when offline) and mobile phone carriers don't care about resilience

[Anonymous No.2567138]

>>2567122
emergency services already tend to use robust trunked radio systems. for normies and their phones, really the best option is to ruggedize cell towers and equip them with UPSes, which I don't see why they wouldn't already just for power conditioning and to withstand normal bad weather.

ham nerds love sperging out about how they definitely saved all of new york during 9/11 but the reality is that grandma isn't going to check in on a CB radio, and excessive radio traffic is a common problem in emergencies as it is.

the exact infra of a given area will give special considerations to how robust it is against catastrophe. If you are in bumblefuck, a downed power pole might take telephone lines with it. In many urban environments, those cables are run underground in conduits and are nearly impervious to most disasters

If it were me and someone raised it as a serious concern, I'd want to implement municipal wifi. Every civic building gets free public wifi, and in case of emergency people are going to flock to those sorts of places and they're ideal spots for emergency services to set up shop to feed/house people displaced by a natural disaster. If their power or telecomms are out, they're a priority to restore anyway.

>emergency SMS-only mode
doesn't matter. it's all data anyway.

>charging personal devices
if people are too stupid to get a spare battery or two then that's their fault. I picked one up for 10 euros and it holds 10 amp-hours and can be fed by either USB C or Micro, with a normal USB A out.

>>2567135
>Do cell-towers wirelessly communicate directly to other cell-towers?
It would depend on the design of the tower
>2G or 1G
modern phones don't support those anymore. 3G is officially deprecated in the US and much of Europe, and Canada wants it out entirely by 2026 iirc.

> each carrier has its own towers.
some are leased from eachother and many countries have rules saying they have to support **all** calls. RoAMinG ChArGeS MaY AppLY

[Anonymous No.2567139]

>>2567138
>3G is officially deprecated in the US and much of Europe
In the US yes but not in Europe.
Recent phones still support 2G (and Edge, the data part) because it's really simple to put that in the chips, it's already developed

[Anonymous No.2567142]

>>2567137
Ok point taken.
I assume some system that can broadcast a message that can be picked up by all clients at once would take less energy than beam-forming a message to hundreds of individual clients. Do you know if it's possible for an SDR to send out a message that any phone within range will receive as a text? I'm guessing not.

>>2567138
>and are nearly impervious to most disasters
Well this is earthquake territory, I wouldn't bet on it.

>wifi
You'd need reasonably large batteries to keep that running for a week, and it only works for people who have been able to get to such a location, and you have the issue of getting an internet data stream to that one location. Starlink could handle the last problem, and a bit of solar and wind could help the first problem. The result being a rather localised solution that uses existing infrastructure. But I hear stories of people trapped by floodwaters on their roofs or in their attics, or trapped in their homes in fear of armed looters (it's a mostly noguns nation I'm afraid).

>doesn't matter. it's all data anyway.
Every second spent transmitting is a second wasting power. An SMS takes thousands of times less energy than a call. If you're trying to conserve cell-tower energy, then restricting it to just SMS-only will go a long way.

>if people are too stupid to get a spare battery or two then that's their fault
Sure that works for a few days, but a week? Two weeks? That's the kind of timespan that I'm thinking about. Because the roads were impeded by falling trees, encroached by flood waters, or totally destroyed by having bridges whisked away or slips pull out from under them.
One part of disaster readiness should definitely be ensuring there's a working battery-powered FM radio in every house with a list of important emergency stations to listen to. Adding a hand-crank or AA battery phone charger to that emergency kit might not be a bad idea.

How cheap could you make an EPIRB?

[Anonymous No.2567143]

>>2567142
>Do you know if it's possible for an SDR to send out a message that any phone within range will receive as a text?
Maybe, not the SMS type but the cell broadcast mechanism, widely used in the world
https://en.wikipedia.org/wiki/Cell_Broadcast
I have no idea it that thing is secured or not, if there's a kind of authentication between the network and the phones

[Anonymous No.2567150]

>>2567142
Again, the actual location of this theoretical disaster matters a lot, and even if you generalize it to rural/urban/suburban/exurb, there's still individual nuance to specific areas and their infrastructure. It's not useful to have a conversation about this kind of thing without more information on the context.

>wifi, batteries
you'd need large batteries for anything you expect to lose power, so this is a bit of a red herring. If it's a city-funded issue, these transmitters should be put in places expected to keep power up anyway, especially places expected to be used for emergency response/gathering.

>internet data stream to that one location
Another reason why context is important. Where I live, the most common disasters are snow/ice storms and hurricanes. Underground stuff is relatively safe. If you're in earthquake land, that's a different matter with different solutions. And they aren't spectrum management solutions, it's civil engineering.

>An SMS takes thousands of times less energy than a call.
Doesn't really matter. Modern phones are always on and cell towers would too always be up to just listen.
There's also already emergency broadcasting services for phones that are activated on demand.

>One part of disaster readiness should definitely be ensuring there's a working battery-powered FM radio in every house
what place doesn't run PSAs about this?

>EPIRB
What do EPIRBs have to do with this? Do you think everyone has RADAR
And EPIRBs are already fairly cheap. Marine versions seem to run about 300 bucks. I think the new iPhone has it as a feature and smaller/cheaper GPS locators for hikers and such already exist.
Any transmitter on certain frequencies will activate SARSAT (iirc it's any integer multiple of 121.5 MHz) but actual EPIRBs listen for RADAR and transmit back on the same frequency, they don't just scream out. They also don't last super long and are mostly to notify your nearest JRCC to get SAR started with a datum to center search on

[Anonymous No.2567154]

>>2567142
>>2567122
>WHY DOESNT THE EMERGENCY BROADCAST SYSTEM EXIST
it does
>WHY DOESNT THE GOVERNMENT PROTECT INTERNETS
robustness against disaster (literally fucking nuclear strikes) was why it was invented in the first place
>WHY DON'T I HAVE A HAND CRANK CHARGER
thats a you problem. i have one. it's shaped like a cute lil' penguin and you squeeze its "wings" to spin a little flywheel with magnets in it :3
>WHY DID MY POWER GO OUT
you live in a shithole country

[Anonymous No.2567155]

>>2567142
>>if people are too stupid to get a spare battery or two then that's their fault
>Sure that works for a few days, but a week? Two weeks?
stop being poor
https://www.canadiantire.ca/en/pdp/rocksolar-80w-solar-generator-kit-with-80w-power-station-30w-panel-5747988p.html

[Anonymous No.2567157]

>>2567142
>How cheap could you make an EPIRB?

...If you're restricted to home because of falling trees or flooding, how would an EPIRB help you?

Also they're like 500 bucks and 90% of that is 100% Boat Tax because everything for boats is hella expensive because only richfags have boats. A chink handheld radio will get you on VHF 16 and you can cry for help all you want on there, people actually do listen.

[Anonymous No.2567167]

>>2567143
I was wondering about that. Not bidirectional, but still really useful. Especially if you can use it to provide localised information.

>>2567150
>places expected to keep power up
So hospitals, probably also freezing-works and server farms but they won't have as much fuel.
>Underground stuff is relatively safe
I guess this is just more "muh context" on my part, but in hilly country like where I am, I imagine it wouldn't be impossible for underground power or data lines to get taken out by slips. A bunch of fresh water pipes from a dam got taken out after all.
>always be up to just listen
My assumption was that the transmit power would be significantly greater than the standby/receive power. Is that wrong?
>what place doesn't run PSAs about this?
Here, it's not hurricane territory like you get in some parts of the USA. Most we learn about is getting to higher ground if we're near the coastline and see the sea receding or feel a quake. Even then we kinda rely on the alert sirens.
>What do EPIRBs have to do with this
Well in the absence of bidirectional comms, if something like the cell-broadcast mechanism is a way of sending information to a bunch of people in potential distress, then the only important part left would be for people in particular need of rescue to be able to actively signal for it.

>>2567154
The emergency broadcasts just said "beware of potential flooding in x areas" and nothing else. There should be much more in-depth information, like which roads are blocked, what areas are dangerous to traverse, where aid is needed, that sort of thing. But an FM radio is good for 99% of that, the only issue being you have to be listening constantly not to miss anything. What I'm more trying to say, is there should be bidirectional communication, preferably a remote bulletin board for people all over the place to share information, but maybe just a way for stranded people to call for help.

[Anonymous No.2567173]

>>2567154
>>2567155
>stop being poor
I said "from the perspective of the local council", e.g. for fucking everybody. I've got solar and all that kit, my fridge didn't even get warm.

>how would an EPIRB help you
By telling a helicopter (or three brown kids in an inflatable) to come and rescue you.
>boat
I was thinking more the sort used for tramping. They definitely dispatch rescue helicopters for those, assuming the local ranger with a satellite phone can't handle it.

[Anonymous No.2567176]

>>2567167
>The emergency broadcasts just said "beware of potential flooding in x areas" and nothing else. There should be much more in-depth information, like which roads are blocked, what areas are dangerous to traverse,
Sorry you live in a shithole, where I live they're usually pretty descriptive and say where an event is happening, where to steer clear of, etc. When it's violent crime related they even have suspect descriptions. Though sometimes it's just "ALELT: BAD SHIT" and then there's an inquiry into why the RCMP are so useless

>My assumption was that the transmit power would be significantly greater than the standby/receive power. Is that wrong?
Cellular networks are very similar to internet/wifi so they're essentially "always on".

>Well in the absence of bidirectional comms, EPIRB!!!
You have no fucking clue what an EPIRB is. An EPIRB is an Emergency Position-Indicating Radio Beacon. It's not a communications device. It's a device you toss off of a sinking ship that shows up on other people's RADAR screens to indicate where you are, that you are in distress, and many models essentially call 911 for you by transmitting to the aforementioned SARSAT. They're registered to ships with a serial number and transmit a code that indicates who exactly is going down (or at least, who owns the EPIRB that's been activated)
It's also a marine/maritime thing, so activating one inland is a good way to eat a fine for misuse of emergency services.

Again, there's similar devices for hikers et al. already in existence, and a few very very new phones can do it natively. They work a little different though.
https://www.hiking-for-her.com/personal-locator-beacons.html

>>2567173
>I said "from the perspective of the local council",
And I said the most graceful solution is to hook that kind of infra up in places that are already planned for use in emergencies to gather people or dispatch support, which will have better protected infra and probably generators.

[Anonymous No.2567181]

>>2567167
>is there should be bidirectional communication, preferably a remote bulletin board for people all over the place to share information, but maybe just a way for stranded people to call for help.
Yeah. It's called a cell phone

last time there was a hurricane in my area, my internet actually stayed up the whole time, lol. Lines are buried so they weren't affected, and the router/modem from bell has a little UPS in it that only got down to like 88% after three or so days of no power. despite not having any lights I was literally able to shitpost on 4chan as long as my laptop lasted and my phone was fine since I had some of those little USB batteries. another time the power was out for a whole evening literally because crackheads stole parts out of a local substation and I didn't even notice because I had the lights off while shitposting and wasn't running anything else in my room with the curtains drawn shut like the gremlin I am

[Anonymous No.2567184]

>>2567176
>It's not a communications device
The ones I've seen transmit their position that they know via internal GPS, though some may just send a data-less ping and rely on that being triangulated. Including an extra few bytes for what sort of emergency it is can't be difficult technically speaking, though modifying the existing EPIRB infrastructure is hardly ideal.
>toss off of a sinking ship
>shows up on other people's RADAR screens
Aren't you thinking of a SART? EPIRBs are picked up by satellite.

>And I said the most graceful solution is to hook that kind of infra up in places that are already planned for use in emergencies to gather people
Yeah it's ultimately going to be ideal to create proper disaster shelters, with radios, cookers, lockers, etc.
But this was a once in 100 year event, and the effected population is just a couple hundred thousand spread between a handful of towns and cities, so I wonder if the councils would even spend that. If the shelters can't be built, or it's infeasible for people to get to them in time, then I think a distributed/decentralised system is better.

>>2567181
>It's called a cell phone
If the 3G cell-towers can have constant power, and honestly that's not that difficult, then yeah it's almost certainly the best option. Then all people need is a way to charge their phones without power, be that solar or a hand-cranker.

>the router/modem from bell has a little UPS in it that only got down to like 88% after three or so days of no power.
Those bastards give you a UPS by default? That's brilliant. Saw some guys trying to hook up 12V batteries to their routers and modems, not sure how they'll like the ~13V a fully charged SLA puts out though.
Wired internet doesn't help if your house is 12 feet under water though.

[Anonymous No.2567188]

>>2567184
>Then all people need is a way to charge their phones without power, be that solar or a hand-cranker.
that's a them problem. and desu little usb batteries and hand crank lights/radios are so cheap they're convention swag tier now. you can LITERALLY get them at the dollar store. i think i have like four now. no hand cranks except a flashlight but I'm in an urban area where if there's something that serious going on, either the army will show up or some local pub with a generator will have all the hot gossip.

if you're mad that batteries/crank devices are still somehow not prolific enough then do a fundraiser or some shit to hand some out for free at a bake sale or some shit. maybe recommend a joint venture with your local fire department, fire departments love that kind of outreach shit and you can probably get financed for a crate of chinkshit hand crank radio-light combo things. they seriously are convention swag tier cheap now. at the local thrift shop I constantly see new ones showing up, often branded with some now-defunct company that makes something entirely unrelated

>Those bastards give you a UPS by default?
the router has its own battery backup inside the device. not all do but it's not an unheard of feature. granted wherever the gateway/dsl/whatever is has to have power too, but again, that kind of place should have generators and redundant power connections. even normal commercial server farms generally do, let alone actual internet infra

[Anonymous No.2567213]

>>2567122
Take everyone off the grid.

[Anonymous No.2567304]

>>2567122
There's a local ham initiative together with some school where they built battery-backed wifi hotspots in the area, connected to a LAN.
The idea is to enable people to go near, connect to the wifi and catch the latest news or leave messages.
Messages that are not for locals can be processed by your ham traffic nets.

[Anonymous No.2567334]

>>2567167
>there should be bidirectional communication, preferably a remote bulletin board for people all over the place to share information
If you're in the country, that's what a 2M repeater network was intended for.
Not just crying about diabetes or talking about omelets, but notifying others of traffic, closures, and poor weather.

[Anonymous No.2567351]

I went to my first lecture for getting a license and holy shit. Why is everyone so fat? They seem like nice people but everyone but me and an old guy are literal fat nerds.

[Anonymous No.2567365]

>>2567040
it may actually be him, he makes duck noises into the mic, interesting

[Anonymous No.2567439]

>>2567351
>everyone is a fat nerd at my how-to-pass-a-multiple-choice-exam-for-idiots lecture
>how will an Adonis like myself be able to tolerate such uncouth rank and files?
>I know! I'll make repeated bait posts on the underwater snail farming forum knowing well it'll be the most attention I get in a given day

[Anonymous No.2567444]

>>2567439
In all seriousness, why are they so fat?

[Anonymous No.2567448]

>>2567351
Where are you from?

[Anonymous No.2567515]

This is going somewhere if you give the direction less significance.
At least the cigars were good

[Anonymous No.2567518]

Do people still care about digi mode monitoring stations or was that just a COVID hobby thing? I noticed all the other multiband monitors shut down within 500-1000km from me. Maybe my 60cm antenna was intimidating but all the other stations had antennas 100x+ bigger, I dunno why they all vanished. My server needs a new mobo but I don't want to spend a month of downtime doing an RMA if people are depending on monitoring services.

[Anonymous No.2567520]

>>2567448
Oklahoma. The dudes looked like they were about 500lbs.

[Anonymous No.2567528]

My radio couch you're not allowed to sit on.

[Anonymous No.2567538]

>>2567528
I bet it'd be a hell of a ride during storms

[Anonymous No.2567542]

>World Autism Awareness Week
>March 25 to April 2

[Anonymous No.2567545]

They're still looking for operators of W2A for World Autism Awareness Week by the way.
I thought /ham/ would be the place to recruit.

[Anonymous No.2567546]

>>2567538
No worries, picrel is the 60 cm tall multiband indoor antenna that feeds it, I'm the only multiband monitor within 500-1000km now for some reason, maybe digimodes aren't cool anymore?
My last base antenna was 50m to the tip up a tree and the coax went over and touched the gas pipe to the house along my bedroom. Thankfully lightning is rare but you could hear and see it build up in your radio before a lightning strike occurs.

>>2567515
I've had tube testers, tube radios, tube signal gens, tube oscilliscopes. I fucking hate tubes and refuse to work on that shit. Through capacitance or whatever you still invariably end up getting shocked when it comes to RF, even with massive cables to their chassis ground going 3' to a 10' groundrod in wet earth filled with electrolyte clay.
Play it safe and only work on tube stuff with one hand behind your back at all times.

High voltage is weird. I built a bugzapper boost voltage ladder circuit and the multimeter voltage at the end read 0v after I had unplugged it and let it rest for a few hours. It still made a massive spark when shorted and was obviously well above the voltage reading abilty of my meter.

[Anonymous No.2567550]

>>2567444
have you tried just memorizing all of the questions and answers using ham study dot org instead of wasting your time at a series of lectures

[Anonymous No.2567551]

>>2567546
>0v after I had unplugged it
>still made a massive spark
That's what's happened to me short-discharging a Whimshurst machine with Leyden jars.
I went away a few feet and touched it when nearing, nearly struck a tooth out with my own hand.

[Anonymous No.2567553]

>>2567550
I don't think you're in a position to question my digits.

[Anonymous No.2567555]

>>2567551
The surviving technicians then go on to learn what bleed resistors are.

[Anonymous No.2567558]

[Anonymous No.2567559]

That Argentina guy. I went 100km on HF with handheld in my driveway to another hill. Coax to the whip and ran a radial pointed their way clipped to the base of that.

[Anonymous No.2567562]

I have an idiotic question and feel free to make fun of me for asking.

How many volts does a 100W station output?

Does it vary based on output power? Or is the voltage fixed at 13.8V and the current sent to the antenna changes?

[Anonymous No.2567569]

>>2567562
uh, well, the idiot in me would say ohms law which would be 70v, the reality is a much higher voltage.

[Anonymous No.2567572]

>>2567562
50 ohm coax & antenna. 100 watts @ 50 ohms = 70v.

[Anonymous No.2567573]

Little thing, but I didn't think it'd be that easy to pick these up. Just getting them with my discone. Too bad I don't speak Portuguese, it'd be fun to listen to. How fast would you get fucked if you tried to use these sats in the US?

[Anonymous No.2567578]

>>2567573
Who knows. I don't trust an SDR to not just report a ghost station that's really on another freq. I picked up someone doing drunk karaoke on mil air frqs, without scanning the band you'll never know where they're actually transmitting vs splattering.

[Anonymous No.2567583]

>>2567578
I reasonably trust it's actual milsat pirates. I don't know portuguese, but google translate picks it up as it. It's FM modulation and I'm in South US so very unlikely to be local if it is portuguese. Frequencies match up to known milsats. I don't have much issues with imaging even on strong FM broadcast stations. It's a known thing too: https://www.wired.com/2009/04/fleetcom/
Recording: https://vocaroo.com/1aChhpm99eTU

[Anonymous No.2567689]

>>2567351
Me and one other guy in our club are the only ones who are not obese. I regularly exercise (mostly cycling and running) and do SOTA activations. The other guy is an electrician who carries heavy ass cords all the time. The rest are couch potatos.

[Anonymous No.2567926]

ARES should require a fitness test to join

[Anonymous No.2567929]

>>2567926
Awwww, did you get rejected by a fatso :(

[Anonymous No.2567945]

>>2567578
>I picked up someone doing drunk karaoke on mil air frqs,
I was recently on a deployment and one of our regular exercises was to just read books over unsecured radio

it was ostensibly for the european navies to practice their english but we all knew it was just schedule-filling and task force command got tired of maneuvering exercises

[Anonymous No.2567971]

>>2566629
So the 818ND went out of production, supposedly due to some components no longer being produced. Does anyone know which one? It is strange to see the prices going sky high when in reality it could become close to impossible to repair.

I hope 819ND will last far longer. Perhaps they will start making their own ASICs rather than relying on a dozen different chips. That could also help keeping power consumption down.

[Anonymous No.2567978]

>>2566155
>Ham needs open source PC software to progress, not overpriced hardware.
I honestly never understood why you need these giant rack units to do audio processing when your PC with its audio jack is RIGHT THERE

[Anonymous No.2568103]

>>2567978
The huge size shown in >>2565862 and >>2565962 relate to having a huge front panel and also many filters. With traditional architecture you would want one filter bank for every single band, and the LC networks (say 5 inductors and 7 capacitors) and related relays take a lot of volume. The Yaesu rig also has a servo operated tuning unit to really home in on that elusive signal, which takes even more volume. Then there is also the autotuner.

Post processing the audio will not recover much if the baseband front end was garbage. And that part is irrelevant anyway if you go for the SDR approach, both for full bandwidth ADC and also ADC on the IF on a superhet, as Elecraft will provide.

The front could be simplified a lot if the designers didn't fetishize buttons. A single large screen with buttons and dials around the 4 edges of the screen would probably be enough. It is not as if people continuously adjust their own microphone setting throughout a contact.

[Anonymous No.2568105]

>>2567978
>It is not as if people continuously adjust their own microphone setting throughout a contact
Have you ever listened to 80m boomers? If they're out of prostrate news, mic settings are everything they ever talk about.

[Anonymous No.2568124]

>>2568105
I have nothing to say, but I want to sound good when I say it.
On CB you're a mud duck stuck in the mud (noise) unless you have good modulation. Mentally you just tune out anyone that's not loud.

[Anonymous No.2568127]

>>2568124
Modulation was an interesting thing when you had to solder your way to sounding good. Now it's buying a good mic and pressing the right buttons.

[Anonymous No.2568158]

>the chad boomer hobbyist
vs
>the digimode babby virgin

[Anonymous No.2568161]

>>2568158
That tube looks bad.

[Anonymous No.2568163]

>>2568158
Also wood is conductive
Thats how wood humidity gauges work

[Anonymous No.2568171]

>>2568163
It's dry, it's a prototype, and I got the proper socket incoming.
Also, the plate voltage is only 90V, it will at least not burn up immediately.
>>2568161
>That tube looks bad
Bad camera and lighting, tube is fine

[Anonymous No.2568177]

>>2568171
>for now

[Anonymous No.2568183]

>>2568105
>Have you ever listened to 80m boomers?
I was in the military and did a lot of HF work

the thing that came up most often after we got voice comms working was "Please stop changing your settings."

[Anonymous No.2568185]

>>2568183
>I was in the military and did a lot of HF work
Nice. I'm trying to gather all the skeds and nets over here where they meet with old military rigs just because it's more fun and most of them know how to fix their shit.

[Anonymous No.2568187]

>>2566629
I thought the 818 was for autistic qrp guys who couldn't carry an extra ounce.
For me, I think the IC-706 was where it peaked. Separated head, hf&v/UHF, 100 watts, large screen, and even a 'scope' akin to an early waterfall.
But a lot of features could be reduced to open source software.

[Anonymous No.2568188]

>>2568185
>skeds
more of a submarine thing but they occur on multiples of 6h... but I don't remember from what time zone. I didn't do sub shit. normal surface fleet (text)message broadcast is 24/7

[Anonymous No.2568192]

>>2568188
Here in Yuropooristan we have small oldtimer amateur nets on regular intervals.
One is a German museum being on air every Tuesday for example.

[Anonymous No.2568400]

>>2567929
Aww, did someone fatshame you being out of breath walking 10 ft again?

[Anonymous No.2568442]

>>2568161
>That tube looks bad.
If you are thinking of the black upper part, that is intentional. It is normally titanium flashed onto the glass during production, after evacuation and sealing, in order to improve the vacuum further by absorption.

[Anonymous No.2568833]

noob here, is it possible to to record the actual waveform emitted by a radio tower. I want to record it and then digitally analyze it on my computer.

[Anonymous No.2568851]

>>2568833
That's what an oscilloscope is for

[Anonymous No.2568854]

>>2568833
Sure, juts use an ADC with proper filters.
People record even GPS signals for later analysis.

[Anonymous No.2568856]

>>2568833
If an SDR's I and Q signals are close enough to the "actual waveform" then an SDR does the trick. If the signal is above ~10MHz then getting an ADC to sample it without down-conversion is gonna be pricy.

[Anonymous No.2568867]

well I'll cut to the chase. I wanna record the signal emitted by some local radio tower and look for echoes from the moon in the signal, basically making a passive measurement to the Moon. Do you guys think it's possible?

[Anonymous No.2568869]

>>2568867
>look for echoes from the moon in the signal
it's possible

[Anonymous No.2569139]

>>2568856
>If the signal is above ~10MHz then getting an ADC to sample it without down-conversion is gonna be pricy.
Let me introduce you to the RTL-SDR.

[Anonymous No.2569504]

Digits decide how I power it up for the first time.

[Anonymous No.2569563]

What did MFJ mean by this?

[Anonymous No.2569586]

>>2569504
Inb4 homeless due to fire.

[Anonymous No.2569643]

>>2569504
Rolling for no fuses or protection diodes.

[Anonymous No.2569646]

>>2569139
the RTL-SDR uses downconversion

[Anonymous No.2569736]

>>2569504
Awww yiiiis, dis gon be gud.

What's your QTH?
I wanna watch your house burn down on the local news

[Anonymous No.2569778]

>>2569586
>>2569643
>>2569736
Up your game, missing the digits. Also
https://youtu.be/sQfViwMkRbE?t=3037

[Anonymous No.2569786]

Do you know where to buy these connectors anons ?
TMP-K01X-A1
They are used in transceivers to connect boards with coax cable. I need one to put a SDR on the IF of my FT-920
google results for the reference are disappointing, or maybe these connectors aren't widely available ?

[Anonymous No.2569790]

>C
>Q
>
>C
>O
>N
>T
>E
>S
>T

[Anonymous No.2569800]

>>2569790
french contest this weekend, the HAM bands are totally unusable
fucking boomers...

[Anonymous No.2569818]

>>2564229
What's the point of this shit hobby exactly? When you have to do everything under your real name and address and can't even encrypt traffic and everyone can listen to you? Are you just LARPing as Howard Stern without even being able to say fuck on the air because the other 70 year old geezer will report you and you'll lose your license?

[Anonymous No.2569820]

>>2569818
You can go in field and spam on different frequencies as much as you want, no need to tell your name.

[Anonymous No.2569822]

>>2569818
it's fun to talk to people all around the world with your own means

[Anonymous No.2569846]

>>2567559
This is very cool. Was it 10 meters?

[Anonymous No.2569898]

>>2569822
What do you think you're doing right now lmfao?

[Anonymous No.2569899]

>>2569898
using a very complex infrastructure I don't own even 5% of

[Anonymous No.2569959]

Thinking about putting a CB on my car so i can talk with my friend. Our houses are about three miles away. How powerful of a machine do i need?

[Anonymous No.2569996]

>>2569818
>Are you just LARPing as Howard Stern without even being able to say fuck on the air because the other 70 year old geezer will report you and you'll lose your license?
lol you have no clue sir
Nobody cares about profanity. Hams are worse than internet zoomers when it comes to insulting each other. It's non-stop feuding and nigger-calling on VHF and UHF and the fcc doesnt give a shit despite everyone knowing each other's identities.

[Anonymous No.2570008]

>>2569800
then tx outside of the ham bands

[Anonymous No.2570037]

Wow the bands are absolutely fucked up today complete silence across 40m and 20m feb 25th @ 15:57

[Anonymous No.2570047]

Hey there are some cute ones

[Anonymous No.2570048]

>>2570047
How many girls are in the hobby? Can I get a chick and talk about how cool my transceiver is?

[Anonymous No.2570050]

>>2569959
That depends which CB band you are talking about, terrain, antenna used and noise floor.

[Anonymous No.2570052]

>>2567351
>Why is everyone so fat?
dunno. one theory is the vilification of saturated fat and the push to use polyunsaturated fats is an underlying cause

[Anonymous No.2570054]

>>2570052
no I eat that shit too and im 140lbs

[Anonymous No.2570077]

>>2570052
i thought it was the food pyramid pushing carbs and shaming fats

[Anonymous No.2570085]

I just fucked up building a 50 ohm 120W load...
Got 2k2 2w resistors instead of 3k3's

I think i might have early onset dementia.

[Anonymous No.2570127]

>>2570085
Just make an 88W load instead I guess

[Anonymous No.2570137]

Can any of you guys help me design a 2.4GHz wifi yagi with as high a gain as reasonably possible? I was following this guide:
https://3g-aerial.biz/en/online-calculations/antenna-calculations/dl6wu-yagi-uda-antenna-online-calculator
But I'm not too sure on the construction. From what I read, it's best to have the elements themselves quite thin compared to the wavelength (3mm is probably too thick), but doing so while being sufficiently strong seems difficult if I'm just using wires/rods held by a boom. Making the antenna on a single-sided home-etched PCB is something I'm definitely looking into, and I bought some SMA connectors for that purpose, but I'm not sure how I'd tune it properly. It would probably be easier to just get a sheet of plastic or plywood and cable-tie wires to it, that way I can easily adjust the length of each element.

The other thing I'm not sure about is the coax balun shown in this guide. Is it necessary, considering the antenna will be mounted maybe a few cm away from a grounded metal rod? What if it's mounted on an insulating rod? Will such a quarter-wave delay work with a wifi signal?

I'm assuming the impedance of the system before my antenna (a modified cheap wifi extender) is all 50Ω, but I can't say that for sure. There used to be PCB-mounted F antennas soldered directly on, which I removed, then I swapped the position of a passive to point instead to the vacant footprint of a U.FL connector, which I have simple antennas on now. The signal seems reasonably reliable, but without a VNA I've no way of knowing how well it's actually matched. Maybe I should wind an air-core transformer and test running antennas at different turns ratios? My shitty RTL-SDR can't see past 1.7GHz so any estimation at signal power is going to be just through connecting to it.

[Anonymous No.2570144]

>>2570085
>I might have dementia
That’s at least half of hams though

[Anonymous No.2570158]

>>2569800
>weekends: contests
>weekdays: contests
>warc bands: dead
It's worse than you think

[Anonymous No.2570180]

Hey guys i have zero knowledge about this hobby but i just found this vintage radio and im completely puzzled on how to use it. Does anybody here know what i have and what i can do with it? Looked on the internet and it apparently is an 80s german radio but i cant find any manuals online. Thanks!

[Anonymous No.2570189]

>>2570180
Looks like a CB Radio (Citizens Band) used to be used by truckers on the road to communicate with each other. My dad had one in his truck when he traveled a lot, a long time ago. I haven't used one in ages so I have no idea if there's still activity on it. It should be fairly simply to use, just turn it on, change the channels and listen/talk.

[Anonymous No.2570193]

>>2570189
>used to be used
still being used

[Anonymous No.2570195]

>>2570189
do you know what the Dx/nah and norm/k9 switches are used for? it doesnt seem to have much use because ive flipped through the channels and theres no activity. you cant really tune in like a normal radio you just have like 20 something channles on it so im not even sure it can receive anything

[Anonymous No.2570196]

dx/nah is probably long distance vs local. it would slightly change how the signal from the antenna is processed.
not sure about norm-k9.
if you're not hearing anything, you probably need to get it in your car and slap the antenna on the roof. then go for a drive on the interstate and look for big rigs. the distance on it is pretty weak and it's mainly used by truckers.

[Anonymous No.2570202]

>>2570189
by pretty weak what do you mean roughly?
feeling kind of pessimistic about the amount of spanish amateur radio truckers near me but ill give it a spin tomorrow as soon as i can find a 12v to 220 converter for my car

[Anonymous No.2570204]

>>2570202
kinda guessing here, but maybe with an antenna mounted on a vehicle roof, about 5-10 miles?

[Anonymous No.2570339]

>>2569504
With a string of 9V batteries like everyone else who plays around with one tube wonders like a chad

[Anonymous No.2570389]

>>2570180
Looks like a generic 80s 22channel CB radio, made by Cybernet Japan. It probably uses PLL02A chip which is easy to mod to have more channels.

[Anonymous No.2570417]

>>2570389
how can i know the wavelengths of the channels this thing has?

[Anonymous No.2570437]

>>2570127
This is what i ended up doing...
Drowned the whole thing in mineral oil in a jar.

Allegedly should be able to take 5 times the power peak to peak now...

Plan to use it for QRP testing anyway...

[Anonymous No.2570464]

>>2570137
>strong seems difficult if I'm just using wires/rods held by a boom
Have you considered using a PCB rather than a free hanging boom? That way you get high precision and can have quite a large number of elements.

[Anonymous No.2570480]

>>2570180
Just coming back to say that i also found this (im gessing it could be hooked up to the radio to play cassette tapes) and a 1936 copy of mein kampf. My gfs parents just bought a house from an old couple with a shitton of german, nazi and fascist spain and italy paraphernalia

[Anonymous No.2570493]

>>2570417
CB is on 27MHz, that's 11m : 300 / 27
As it seems to be a German CB :
In Germany, the frequency range is between 26.565 MHz - 27.405 MHz (80 channels), in Europe between 26.965 MHz - 27.405 MHz (40 channels).

[Anonymous No.2570497]

>>2570417
and here are the frequencies of each channel
http://fldx.org/site/ger-cb-channels.php

[Anonymous No.2570551]

>>2570180
Hi germanradio anon here i was able to get some Dx signal but its all very noisy and low quality and ive noticed the swr meter is at like 6 on dx signals and 1 on low signals but it can get pretty high when using dx. ive looked around and that seems to be a big problem(?) when i transmit with the microphone it just goes straight to the max and that apparently can fry the radio right? im not transmitting much just in case.
is it a problem with the antenna? i unscrewed the coax cable and it looks like this as stated i am a total noob and i dont even know if the end should look like that theres some sort of brown resin at the tip.

[Anonymous No.2570555]

>>2570551
>swr meter is at like 6 on dx signals and 1 on low signals
The "Nah/DX" is probably a switch for either a preamp or an attenuator.

[Anonymous No.2570557]

>>2570555
yeah nah seems to be short for nahe wich is near in german. found out that norm/k9 is just a switch to go straight to channel 9 which is the emergency channel in cb radio.
do you know if i should worry about the needle in the "instrument" panel going to 8-10?

[Anonymous No.2570561]

>>2570555
Nah, same as nahe, yes, "close" opposed to "DX" - "distant"
>norm/k9 is just a switch to go straight to channel 9
Yes.
>worry about the needle in the "instrument" panel going to 8-10?
That means you're receiving a strong signal, but doesn't sound bad to me.
But it's S1 to S9 and the "+10" is that it's "10dB over S9". You will hear that often when people report signal strengths to each other.

[Anonymous No.2570563]

>>2570561
meant to reply to (You) >>2570557

[Anonymous No.2570569]

>>2570561
thank you man youre really helpful. do you have any tips to be able to listen to a broadcast without it being a noisy mess? i can get a couple of channels with chatter but its indistinguishable.

[Anonymous No.2570570]

>>2570569
Perhaps it's because the B54FM can only do FM, it can not demodulate AM or SSB.
Find a channel where they use FM to talk.
It's also possible that it's not stable on frequency anymore or some circuits are broken.
Here's about it:
https://www.radiomuseum.org/r/dnt_cb_basisfunkgeraet_b54fm.html

[Anonymous No.2570582]

>>2570570
could i get a cheap walkie talkie to test out if it can work?

[Anonymous No.2570584]

>>2570582
Probably, but don't transmit too close, get a friend to move away a block and talk into it.
Or disconnect all cables and antennas, with some luck it receives a signal.

[Anonymous No.2570587]

>>2570584
do you mean disconnecting the radios antenna and transmitting with the walkie near it?

[Anonymous No.2570595]

>>2570587
Yes.

[Anonymous No.2570603]

>this thread

[Anonymous No.2570635]

>>2570464
...yes
Because that's the very next sentence. I'd be fine ordering a board from JLC for it if I knew it would work for certain, but I just don't have that confidence when literal millimetres could make a difference.
Also pcbs aren't that sturdy, especially if I go for like 20 or more elements (almost a metre long). the thing will be vertically polarised so wind catching a flat directional card like that could be a real issue.

[Anonymous No.2570668]

Picked up this the other day. Red Pitaya clone. Still working my way around it, the software support is atrocious but I might try to bang my head against the wall enough to get something more workable out of it since the receive ability of this appears to be very good. Better than my RSPDX at least. It seems to be popular in Germany and Russia to use these as a base for a fully fledged HD SDR transceiver, I don't see much for English speaking countries. I'd like to do the same but that's probably biting off a little much for my current skill level.

[Anonymous No.2570743]

>>2570339
>>2569643
>>2569586
>>2569736
I powered it up today, no house fire.
But it also wouldn't want to give a sound out of the earphones other than a buzz.
Funny thing is on the filament circuit, even with anode voltage still at 0V, it displayed 6V instead of 1.5V when I switched to TX from RX. Yet, the filament wouldn't even start to glow. I hope the tube isn't broken.

[Anonymous No.2570851]

I'm kinda satisfied, having bought some oldschool 1MHz RF Synthetizer Frequency Generator in the aim to learn transmissions and see how it goes with my KiwiSDR, check my antennas in that low spectrum and whatever experiments with AM and crafting own circuitry TX/RX for fun.
Is there guides to recommend for someone with university background in math, physics, and soldering shack?

[Anonymous No.2570863]

>>2570851

As far as a receiver goes, you can build a diode ring mixer.to demodulate a analog signals. Nobody uses AM anymore apart from some religious fridge kooks.

You can build a CW transmitter with a crystal oscillator and a transistor. A fun and easy one is called "Ten Minute Transmitter". You can probably guild one from garbage you have around the house. It's super low power, but you can stick a mosfet,or several on the output and get some respectable output. It can be modified for AM easily by adding a microphone and op amp to the emitter.

You might want to beef up your signal generator, to something with at least 10Mhz - 30Mhz if you want to listen to the popular HAM bands

[Anonymous No.2570882]

>>2570743
What tube? Those 1.5V filament battery tubes have a barely noticeable glow, gotta be in a dark room. They're also easy to burn out

[Anonymous No.2570888]

>>2570882
>They're also easy to burn out
That's what probably happened.
The glow is noticeable on an overcast day, I've kept a voltmeter in parallel to watch the supply.
I just don't get how I measured 6V other than a higher resistance. Can it be a cold solder spot on the way?

[Anonymous No.2570892]

>>2570882
>What tube?
I forgot, a CV808 double triode

[Anonymous No.2570907]

Just acquired all this. Can I talk far?

[Anonymous No.2570912]

>>2570863
thanks for those nice tips I'm gonna dig harder on those points
>"Ten Minute Transmitter"
that DX explorer is a good trip for nights.

[Anonymous No.2571010]

>>2570907
>gay retard troll again

[Anonymous No.2571012]

>>2571010
No sir. That's the first time that image has been posted to the internet.
I used to be a radio repair man. Then the radio guy for my platoon in Iraq. I've forgotten so much

[Anonymous No.2571028]

>>2570668
>the software support is atrocious
does it not just work with gqrx? or anything built with gnuradio?

[Anonymous No.2571070]

>>2570907
wow, nice, you need some good antennas, especially yo use the amplifier, not all antennas can withstand the power

[Anonymous No.2571129]

>>2570668
I have one of these
>>2571028
It works with both of them. It uses the RedPitaya firmware http://pavel-demin.github.io/red-pitaya-notes/ no idea what he is talking about the "software support being atrocious"

I'm going to build an RX frontend for mine soon

[Anonymous No.2571130]

>>2571129
well I should be a bit more constructive then that. if you are having issues with the software make sure to use the latest release from here: https://github.com/pavel-demin/red-pitaya-notes and load it on to the TRX-DUO. If you are on Linux you can use GQRX if you set it up as a SDR receiver and on Windows you can use RTL-SDR or SDR++. If you want to TX you can use GNURadio or Thetis SDR (which absolutely sucks) but I'm also looking at different ways of setting it up to transmit.

[Anonymous No.2571191]

>>2570668
>>2571129
Is there a Red Pitaya-like device with 4 separate inputs? With at least 4 it should be possible to do direction finding and beam forming.

[Anonymous No.2571208]

>>2570882
Checked the tube today, filament is fine
Checked also: my digits >>2570555 >>2570888

[Anonymous No.2571247]

>>2571012
>I'm an expert radio repair man and was a spark
>huuurrr can I talk good with pic related
Sure thing, bud.

[Anonymous No.2571248]

>>2571208
>digits
go fuck yourself

[Anonymous No.2571251]

>>2571247
not him, radio repair in the army consists now to replace SKUs with a new one or send the hole unit to the manufacturer

[Anonymous No.2571254]

>>2571247
NTA, but what is implausible here? A lot of people I know got their licence in the military.

[Anonymous No.2571259]

>>2571254
follow the reply chain, retard

[Anonymous No.2571293]

>>2571248
seething boomer detected

[Anonymous No.2571508]

[Anonymous No.2571512]

>>2571508
auto notch is wonderful

[Anonymous No.2571527]

>>2571508
We have 'stomps' on CB where everyone piles on until they get called, then the receive stations changes to somewhere else after going through everyone. All the points are tabulated and everyone gets a final ranking for the night.
I went to the vehicle stomps and competed in the 2 pill class. The person I was competing against bled against my transmitting radio so hard that its internal speaker was repeating THEM while I was transmitting. How embarassing.
Everyone likes to shit on CBers but they do weird stuff like trailer hitch yagi front and back of the car, 16 pill amps or 20 alternators in a suburban to power 20kw+ tubes.

[Anonymous No.2571736]

>>2571130
GNU Radio doesn't look too hard to write an implementation for yourself, but I haven't tried using it.

>>2571191
custom firmware for starlink base-station when?

[Anonymous No.2571913]

I'm loving FT8. I got all 50 states in 2 days along with plenty of DX contacts. So why all the hate from boomers?

[Anonymous No.2571972]

>>2571913
2 days? Dangit. Did you log them? Took me like 2 months in the summer but I guess winter conditions are better.

Similar to the Red Pitaya, the Hermes has support with SparkSDR which will let you do FT8 and whatnot.

>>2570851
SI5351 breakout boards are just a couple dollars and will output 8khz - 160mhz (square wave). It's what the NanoVNA's and the cheap transmitter/transceiver kits use. Has roughly the same output power as that signal generator. For giggles I attached a clock and antenna directly to it and got about 5000 km on FT8.

[Anonymous No.2571974]

Any DIYers here or you just buy off the shelf radio stations?

[Anonymous No.2572008]

>>2571974
There's plenty of DIY, here's my DIY slinky antenna and balun. You don't need to reinvent the PC before you can be a programmer. Handheld 2m stuff is mostly boring tho aside from that guy that was trying to setup an alarm system with some baofengs.

https://w1sye.org/wp-content/uploads/2017/01/NCRC_PixieOperation.pdf

That's a basic transceiver. You can expand on it by using a PLL instead of the crystal. Using relays on the output to switch between different band filters.

High power RF transistors/mosfets are expensive tho. Probably looking at $100-$200 for the one in a normal radio. https://www.rfparts.com/sd1446.html . Spurious emissions and whatnot can get you in trouble if you don't add enough filtering and you're kinda just guessing how bad it is until you actually measure it yourself with expensive equipment.

Shit like baluns, antennas and manual tuners are where the bulk of the DIY is. Just a modest assortment of torroids cost me like $300 to buy.

>>2570551
The brown crap is solder flux. Brush and alcohol will clean it off.

[Anonymous No.2572015]

>>2565966
from that era, they're probably crystal-locked on 49 Mhz FM

[Anonymous No.2572020]

>>2572008
I've checked and standard crystal oscillators can go up to around 60MHz. How do those small 433Mhz transceivers get their frequency? Same question about 24GHz transmitters.

[Anonymous No.2572026]

Can probably reference the FCC ID #. I'd guess it's around 27mhz. RM italy has single mosfet amps with push button or autosense triggering and their board etching templates and schematics are readily available. The mosfets are cheap and I'd get a few of them for a dollar.

Here's a mini altoids tin amp with relay activated RF autosense triggering using deadbug construction. You can make it 50-80% smaller if you remove the relay/autosense and trigger off the existing push button on the radio. Personally I would use a socket for the mosfet so you can replace them easy as you burn them up, lol.

[Anonymous No.2572027]

>>2572020
>How do those small 433Mhz transceivers get their frequency?
Harmonics or, more likely, a phase locked frequency synthesizer. They generate multiples of the base frequency, see Si5351.

[Anonymous No.2572038]

>>2572027
What about those 24Ghz oscillators?
https://aliexpress.com/item/1005004848239174.html
If there's cheap as fuck 24Ghz oscillator, why there's no cheap like 12Ghz ones for example or cheap 100Ghz? All this high frequency conspiracy makes no sence to me, to be completely honest.

[Anonymous No.2572039]

>>2572020
Mixers. https://www.rfwireless-world.com/Tutorials/RF-mixer-basics-tutorial.html

https://philcrump.co.uk/images/0/06/Elonics-E4000-Datasheet.pdf

[Anonymous No.2572041]

>>2572038
24ghz is an ISM band, 12ghz is not https://en.wikipedia.org/wiki/ISM_radio_band

[Anonymous No.2572044]

>>2572041
It's not about particular number of Herz, it's about the conspiracy that high frequencies are expensive. Then why can I find dirt cheap high frequency chips? It almost looks like this industry doesn't want to share and pretend how hard and expensive everything is. Makes no sence to repeat this bullshit. Sooner or later we will talk about hundreds of GHz.

[Anonymous No.2572053]

>>2571974
I'm trying to make my own transceiver, and did a few portable antennas myself including ununs.
I also fixed a boat anchor after it broke down two days after I picked it up
>t. ohmlet
I have no idea what I'm doing most of the time

[Anonymous No.2572054]

>>2572044
Learn on HF first.

[Anonymous No.2572056]

>>2572053
You can't improve what you can't measure.

[Anonymous No.2572064]

>>2572056
>insightful
but also
>random

[Anonymous No.2572075]

>>2572064
Make a transceiver only if you're rich and bored.

[Anonymous No.2572079]

I've seen different transmitters write their amount of power. Something like 25 mW. Can you make a really powerful transmitter in a common band? Say 10W?

[Anonymous No.2572080]

HAMfags, is it possible to build something that will passively invert a received carrier signal 180 degrees out of phase and rebroadcast it to create a null spot? Like with a transformer somehow? Asking for a friend.

[Anonymous No.2572104]

>>2572080
You will end up with a lot of broadband QRM and a residual carrier except on location, and there any receiver will be blocked by the 180° carrier anyway.
You're better off with a high-Q bandpass or notch filter depending on what you want to receive compared to that carrier.

[Anonymous No.2572106]

>>2572075
I'm talking about a single-bander qrp tube trx, not a full-blown rig.

[Anonymous No.2572111]

>>2572106
>tube
No. Only experts should play with tubes. RF burns destroy the eyes and the testicles first.

[Anonymous No.2572113]

Fun fact. RF burns don't hurt above 500khz or so, your pain receptors can't respond quickly enough to it. You should deal with as low of voltage stuff as possible.

[Anonymous No.2572115]

>>2572113
>>2572111
As if hf coming out of a tube tx is any different than from a solid state one

[Anonymous No.2572123]

>>2572115
>As if hf coming out of a tube tx is any different than from a solid state one

Bitch, touch a 12v battery with your hand, does it hurt? No. It's too low of voltage. Cutoff is around 40v.

Touch a 120v outlet with your hand. Does it hurt? Of course it does.

Everything has capacitance, especially high voltage stuff which tubes use, Because we're dealing with AC this leads to power being wirelessly transmitted, most notably to the cases of things. A simple ground doesn't work as the wavelengths of the ground wire determines its impedance.

Fuck tubes. Working with one hand behind your back sucks.

[Anonymous No.2572124]

>>2572123
>Fuck tubes. Working with one hand behind your back sucks.
I see where your grief is coming from.

[Anonymous No.2572132]

>>2572124
We can easily visualize and measure DC, like water flowing smoothly. AC is a spurting hose that splashes on everything instead and otherwise does weird shit. Don't ever trust a meter to read anything but 0v when you're dealing with 1kv+.

[Anonymous No.2572138]

>>2572038
At high frequencies I guess a synthesizer is not fast enough. There are other designs:
https://www.cambridge.org/hn/files/5413/6698/2360/HFIC_chapter_10_HF_VCO_design.pdf
There are also Gunn diodes.

Above 3 GHz, designs become very complex and everything becomes waveguides with lots of parasitic problems. Such designs are heavily specialised.

[Anonymous No.2572147]

Has anyone with a uSDX+ v2 tried installing the missing 100K resistor and is able to confirm whether or not there are any improvements?
https://www.youtube.com/watch?v=oPDza8W7pGQ

[Anonymous No.2572163]

Post dummy loads.

[Anonymous No.2572363]

what books should i read as an absolute beginner? not looking to get my license this soon, but just dipping my toes in and getting a general understanding of things.

[Anonymous No.2572395]

>>2570008
Love the '690S. My favourite rig.

[Anonymous No.2572485]

dummy loads.

[Anonymous No.2572546]

>>2572363
In te library, you will find a book called
>CRYSTAL SETS TO SIDEBAND
>A Guide to Building an Amateur Radio Station
That is the book for you.

[Anonymous No.2572668]

>>2572546
This, it's a great book.

[Anonymous No.2572757]

>>2572395
>My favourite rig.
That reminds me, any updates from the Freeplane diagram anon?

[Anonymous No.2572776]

>>2570054
>>2570077
This. I don't shill keto but I stopped eating simple carbs a couple weeks ago (basically just been eating eggs, meat, vegetables, drinking milk, coffee, and water (and sometimes whiskey)) and I've dropped like 15 pounds. More energy, hungry less often, eat less when I'm hungry. Can't say it'd work for everyone but it's going okay for me so far.

[Anonymous No.2572786]

>>2571972
Aren't square waves basically unusable at frequencies near your ADC sample frequency? You get those harmonics messing with you. I'd like to see a nice sine-wave frequency synthesiser in the same price range as the Si5351, if just for the <100MHz stuff. I'd settle for a discrete sinusoidal VCO to make my own PLL out of in addition to a 5351, but I'm not sure if traditional sine oscillator topologies are stable over more than a decade of frequencies.

Doing some sorta meme variable frequency filter (switched capacitor?) to follow the square wave frequency to keep down the harmonics might be cool though.

[Anonymous No.2572809]

Does anyone build antennas here
I am requiring about 20 antennas of about 16dbi for 5.2ghz and due to budgeting reasons, I would like to just build them using bits.
I've built 2.4ghz yagis before and they worked great so idk.

I found a yagi designer and put in some info but I have no idea if anything is going to be correct.
The bend diameter of the folded dipole seems to affect resonant frequency but I have no idea what value is correct

[Anonymous No.2572890]

>>2572809
>I've built 2.4ghz yagis before and they worked great so idk
Can you answer any questions here: >>2570137

For price reasons I'd try to make a PCB antenna, though I'd construct it in an EM simulator to test it out first.

Any reason to use a folded dipole over a straight one? Is it more directional?

[Anonymous No.2572921]

>>2572890
Yes use this or something. Same one I made long ago. Should be good for 17ish dbi
3mm is far too big, for 2.4 like 1.8mm or 14ga copper works great. On 5ghz I think it needs to be very small ideally, 22ga, 0.6mm maybe. Should be fine for either because the wire length is so short.

Idk folded dipole is what yagis use.

[Anonymous No.2573093]

yey. 0-1hz of error across all of HF now using multiple RXs. Not bad for 0.5ppm TCXOs . WSJT freq cal was way more sensitive than other tools I was trying, getting 20 better SNR on the time signals.
https://www.qrp-labs.com/images/wsprnet/rxerror.html

They update that page every 2 mins if you want to check your own error rate using wspr.

[Anonymous No.2573115]

>>2567042
It would work its just fucking stupid and more infinitely more prone to malfunction compared to a dedicated repeater

[Anonymous No.2573133]

>>2572080
Yes. Theres a QRM kit on amazon for noise cancelling, its basically the MFJ one.

[Anonymous No.2573206]

>>2572776
no one cares fag
go blog on >>>/fit/

[Anonymous No.2573415]

>>2573206
You're not you when you're hungry, you terrible fucking cunt. Go eat a couple of fucking donuts.

[Anonymous No.2573516]

>storm in the area
>listen to the net check-ins
only thing amateur radio is good for

[Anonymous No.2573658]

>>2573206
>no one cares fag
>go blog on >>>/fit/

[Anonymous No.2573718]

I've read that the radiowaves cannot penetrate the boundary layer around a supersonic moving object. But how do rockets and supersonic aircrafts operate radars and get GPS coordinates?

[Anonymous No.2573735]

>>2573718
That is only when the speed is so high (Mach 11+) that the boundary layer becomes ionized.
F-35 does barely Mach 1 in supercruise for only a brief period, Mach 1.6 with afterburners, so it is nowhere near ionizing the boundary layer.

Air intercept missiles reach Mach 3 - 5, still a long way away from the problems. Only space vessels in reentry and incoming ICBMs can reach such speeds, but only for a short period before intentionally aerobraking to lower speed.

In any case, with a 3+ megaton warhead, high precision is not needed.

[Anonymous No.2573737]

>>2573735
Thanks. So if I build a rocket that goes Mach 2 it should be able to log its GPS coordinates?

[Anonymous No.2573898]

>>2573737
It should.
The onøy propblem is that commercial GPS receivers have limitations added to them in that they stop reporting once they exceed an envelope defined by speed, accelleration or altitude. Of course, an open source GPS receiver need not have those limitations.

[Anonymous No.2573904]

>>2573898
I've suddenly got a lot more questions.
Firstly, the fuck is this
> ø
Secondly, what are those limitations or how can I google it?
And finally, you can build an open source GPS receiver??? How?

[Anonymous No.2574071]

>>2573904
You're in an amateur radio thread and you don't know what 'ø' is?

[Anonymous No.2574090]

>>2564345
He has a mess of testicles

[Anonymous No.2574102]

I want a VNA that goes up to at least 5GHz, and also an SDR that does the same. Am I able to buy a single thing that does both? It would appear to me that a lot of the hardware in them is the same, at least for an SDR with both TX and RX.

But reading this:
>https://www.rtl-sdr.com/rtl-sdr-tutorial-measuring-filter-characteristics-and-antenna-vswr-with-an-rtl-sdr-and-noise-source/
It looks like a noise source and a receiving SDR is all you need, as opposed to feeding out a sine wave at the specific frequency being measured. Is this how VNAs actually work? I don't see how you'd get phase information from that.

[Anonymous No.2574178]

>>2574102
>an SDR that does 5GHz
The ADALM Pluto module can do 70MHz to 6GHz with the "hack". It's built around the AD9363 chip which seems to be a binned version of the slightly better AD9364, so you can tell the Pluto it's using the AD9364 and you open up the extended frequencies. Because the AD9363 is probably the AD9364 that didn't quite make the grade, YMMV.

[Anonymous No.2574180]

>>2574102
>s this how VNAs actually work?
No they generate a sine wave of the desired frequency or sweep from min to max freq

[Anonymous No.2574249]

>>2573904
>I've suddenly got a lot more questions.
Much is in the FAQ
>Firstly, the fuck is this
>> ø
A typo. Should have been "l" in "only". "ø" is equivalent to "ö".
>Secondly, what are those limitations or how can I google it?
Military limitations. See
https://en.wikipedia.org/wiki/Coordinating_Committee_for_Multilateral_Export_Controls
>And finally, you can build an open source GPS receiver??? How?
Sure. Easy mode is to use this design:
http://www.aholme.co.uk/GPS/Main.htm
It does L1 only but works. It is also used in the KiwiSDR receiver in order to get a good time and position fix, and thus use multiple receivers in emitter localisation. Unfortunately this receiver is getting hard to obtain, I think some components are no longer available. Hopefully Kiwi2 will be made soon.

[Anonymous No.2574266]

>>2574249
>Easy mode
>FPGA
bruh...

[Anonymous No.2574373]

>>2574266
Sure. All the components and sources are out there.
I had hoped this would have been revise to also handle futher bands such as L2C and L5. It is possible to make multistatic radars with this using the GPS satellites as transceivers. People have even used this to determine moisture contents in the atmosphere.

[Anonymous No.2574718]

I'm trying to listen to local ems dispatch, they use narrowband FM so I was looking at the RSP1A sdr, I want to stream it to broadcastify from a raspberry pi. I've been doing a lot of reading but I'm a noob. Is software picky about which dongle you use? Like will this only work with some programs or should it generally work like an rtl sdr dongle? Also will my tv antenna be able to pick up frequencies around 155mhz? It can pick up fm radio but I'm not sure if it's quite the same, again, noob.

[Anonymous No.2574719]

I was thinking that a LoRa node with wifi would be a neat way to communicate long-range even with disasters. If I put a LoRa gateway atop the hill overlooking my town it would probably get the entire area. There are already LoRa nodes about the place, but I've no idea if they'd be resilient enough to run without the power grid for days.

The idea is each node would just be an ESP-12F and an Ra-01SH, with the ESP broadcasting a wifi network. You'd connect to it via a cellphone and go to the webpage written on the node. There would be a backlog of conversations (probably just in the few MB of mostly unused flash on the ESP-12F) and a way to start new conversations by entering an ID number and message. 160 character limit or less, ASCII only, that sort of thing. SF-12 has a bit-rate of 250b/s, so if you send a full message of 160*8b that's 5.12 seconds (not including CRC). With the 1% maximum node use, that's basically one message per 9 minutes, which is kinda shitty but not unusable in an emergency.
Maybe compressing the text down into 6 bit alphanumeric would be worthwhile. Or even some sort of variable-bit-length encoding (e.g. morse but actually informationally dense), or a "caps-lock toggle" symbol.

[Anonymous No.2574772]

>>2574718
Me again I solved my question about software, it appears that I'm able to do what I want to do with the RSP1A. Still wondering about using the TV antenna to pick up narrowband fm frequencies around 151-156mhz though

[Anonymous No.2574785]

>>2564229
What kind of project could you make with commercial units like >picrel.jpg (bs410 I think)?
I have a couple of olds tv-fm cards packed with the bt878 chip.
Can you do SDR with that?
Are the Uniden BCD325P2 type scanners a go?

Thanks

[Anonymous No.2574867]

>>2574785
Probably nothing too fun without a crazy high time investment.
While the chips could in theory be tweaked to capture different bands, the support circuitry would bee too much work / cost more compared to just getting a USB dongle with all the functionality build in for 10$

[Anonymous No.2574873]

>emergency net going on due to natural disaster in the state
>people passing traffic along
>a contester barges onto the frequency without saying "is this frequency in use?"
>just literally blurts out "CQ CONTEST CQ CONTEST [callsign] CQ CONTEST"
>stomps on everyone due to obvious use of an amplifier
Contesters deserve the rope.

[Anonymous No.2574880]

>>2574873
Imagine having anything less then 5kw of power available and trying to "help".
Unless your sterilizing birds mid air you should have no part in the emergency network.
Unless our emergency broadcast is actively disrupting out air traffic control frequencies across south America is it really an emergency?

[Anonymous No.2574888]

>>2574873
>without saying "is this frequency in use?"
>just literally blurts
>Contesters deserve the rope
You're not wrong, anon

[Anonymous No.2574925]

Can you explain me something?
Lets say there are two engineering teams with equal RF capabilities and knowledge, and you come to them with your 2.4 GHz device and tell them to design a directional patch antennas for maximum range L. Will they come up with the same antenna size and shape because there is an optimum solution?

[Anonymous No.2574927]

>>2574772
It's totally impossible, an empty-set, does not exist, 404 error . . .

[Anonymous No.2574930]

>>2574925

[Anonymous No.2574934]

>>2574925
Please help.

[Anonymous No.2574951]

>>2574927
I feel like you're being facetious.

[Anonymous No.2574964]

>>2574873
>emergency net going on due to natural disaster in the state
>people passing traffic along
Emergency agencies all have their networks, that is absolutely unnecessary. It's a hobby and HAMs will not save anyone ever

[Anonymous No.2574976]

>>2574964
I have no idea where you live, but around here, /ham/ operators are used to establish emergency communications.
Too often cell phone base stations have gone down, the governmental TETRA system collapsed (equipment is being blamed) and land lines are kaput.

[Anonymous No.2575145]

Will a magnetic loop antenna made out of tv coax and a tuning capacitor work for receiving? Not sure since the shield is made of aluminum and the ones I've seen are from quality coax

[Anonymous No.2575160]

>>2575145
>Will a magnetic loop antenna made out of tv coax and a tuning capacitor work for receiving?
Yes. You don't need the capacitor but it'll give you much better SNR.

[Anonymous No.2575393]

Found a lot of cable last night. There is RG6 TV coax in the mix. How feasible is it to use it as a 43ft vertical antenna? Should I still use a 4:1 balun as the guides for the 43ft vertical guides say? How many radials should I use and how long for 160-40m? Do I need to strip off the insulation?

[Anonymous No.2575422]

>>2575393
>Do I need to strip off the insulation?
With old coax you have a lot of options. Just use the coat as antenna, strip the coat off and use the center as one.
There are certain antenna designs using coax as radiators in a more sophisticated way, like pic related
https://m0ezp.squirrelhouse.biz/coaxial-dipole-40m-aka-double-bazooka/

[Anonymous No.2575424]

>>2574925
Bump

[Anonymous No.2575499]

Hello friendly /ham/ers,

I'm starting the basic step before installing antennas on my rooftop: Grounding to earth.
My question is quite simple: Do I need to draw a distinct line away from the home's grounding line ?

Having read some comments about lightning, do you set up some circuit breaker between antennas and its receiver to cut everything easily under storm ?

I live 30m away from a lightning arrester that culminates at 25m. In Theory, it has some thorium spike on it, nah ?

and maybe a last question. I plan to set up some antennas near of an already installed Starlink's Dishy, which crawl between 10-12Ghz. Could I experience some noise problem ?

[Anonymous No.2575517]

>>2575499
>Grounding to earth
it is useful only to solve problems related to that. You need a RF ground : not just a rod in the earth but a mesh of cables on at least a couple of m2
What part of your antennas will be connected to that RF ground anyway ?

[Anonymous No.2575611]

>>2575517
>What part of your antennas will be connected to that RF ground anyway ?
J-just the tip

[Anonymous No.2575648]

All the best 73's and warmest regards to you and yours.

[Anonymous No.2575738]

>>2575648
>thanks, bye, qrz contest?

[Anonymous No.2575790]

>>2575517
Maybe this is also why bridges are awesome.

[Anonymous No.2575791]

>>2574867
I just disassembly one to roam it , but I was thinking more or less the same, it's less of a hassle to go for the usb dong.

[Anonymous No.2575890]

DASH7 isn't really the Plan 9 of the link layer, r-right?

[Anonymous No.2576039]

SWITCH CHANNELS >>2576037
Kchyuuu Ass Why >>2576037
Angry boomers have a fix on your location >>2576037
NEW THREAD >>2576037