/diy/ - Do It Yourself

>>2393649
These days I am a consultant, but I was in the military when i learned Morse code and got the license.

>>1916715
CB is mostly dead, hams never engaged in that from what I heard, at least I never experienced it ever.

Old rigs, especially boat anchors such as pic. related are still popular with collectors.

I see a R-390 for sale, about USD 450. I checked eBay for reference but prices are all over the place. So, is this a good price or not?

>>1702318
Most of the hams I know are ex military guys who are quite familiar with security and know what an ambush is.

>Good morning Mr. Phelps
>Lately the ham radio technology has become stagnant. Very little has happened on the analogue front end beyond what we knew with R-390A/URR. At the same time DSP technology is a mainstay of mobile telephone technology. Short of some modest developments on digital modes, very little DSP innovations can be seen in radios. The Secretary has decided this cannot continue.
>Your mission, should you choose to accept it, is to construct the R-400/ORQ.
>As always, should you or any of your IM Force be caught or killed, the Secretary will disavow any knowledge of your actions. This ka-baomfeng will self-destruct in ten seconds.

OK, what do?

>>1451134
Pic. related is Boat Anchor grade vintage, mil. spec. rugged and works fine. it is from long before the 90's.

Following up from last thread:
>>1349124
>What do people speak about on CW? Or it is used for QSOs only?
You can easily use it for chatting, after all it is faster than texting/SMS: https://youtu.be/pRuRE-Bwk1U
>I mean, how is CW-shitposting?
OK, this is so many years ago now that it can be told:
>be me. in uniform. in the military
>On exercise, running traffic using voice. It is late, it is boring and we are getting tired.
>Suddenly: a burst of Morse!
>Immediately awake, perking up, locking onto code. It is a mild case of poo posting. Woo hoo!
>Notice higher officers around. Noticing none of them are Morse capable. Keep straight face.
>Another burst of Morse!
>A few hours later about half the traffic is Morse, yet keeping exercise traffic up still. Higher officers only care about getting (real) traffic through. Still suspicion is growing
>And they sure had good reasons for it!
>Exercise over, everyone pretending Morse never happened.
Telegraphists flouted a lot of rules but we were accepted as long as we delivered and that we did, especially during heavy jamming.
Officer 1: "They really should dial back the jamming; it just brings the exercised to a grinding halt!"
Officer 2: "Really? We got every traffic through" . o O ( Smirk )
Officer 1: . o O ( Groan! )


OK, enough reminiscing, back to thread.
>Also I have a question about FAQ. There's sentence:
>>And make no mistake, you will be found. And recorded, voice prints archived for future use.
>but
>>A properly trained military Morse code operator will know how to transmit to the target without being caught by enemy intelligence
>So, are Morse code operators caught or not?
There are two different issues here: one being recorded and (roughly) located, the other being actually caught. This is literally the difference between life and death.
>I guess, uncatchable one must have 5 years of military education?
You need wide training but it probably takes less than 5 years.

>>1341202
(2/2)
>>the frequency might be OK for some DF tests I'd like to do
>consider chinkshit AD9850s if all you need is CW tx on a fixed frequency. you won't need a whole lot of filtering to clean up
Yes, I want to do CW and digital modes, not voice.
>>Just why?!
>I believe
>>inb4 stop making shit up
>PIC, Arduino, Pi, etc. are mostly the thing in ham due to the small overlap between digital and RF electronics. the large volume of literature and lore going back 20 years or more, with PIC's foray into ICSP, made it a no-brainer choice over the other main commodity option, which was an 80C51 with a full address/data bus and EPROMs. AVR was sadly a latecomer and somewhat under-represented, but STM32 seems to be picking up some speed these days thanks to, among other things, megasample DACs
Unfortunately these are also power hungry and not suitable for portable use. Qualcomm wants to engage the community, they say, yet they keep the prices unbelievably high and documentation close to inaccessible. Mobile phone chip sets are highly optimised for low power consumption while delivering good DSP power.
>>using one with a pixie
>in the pixie, the crystal's role is cleverly switched back and forth between the inductive element in a Colpitts oscillator (for Tx) and a narrow band-pass input filter (for Rx). thus, a real crystal or other high-Q resonator is required. maybe you could usefully pull it to the next channel with a varactor and a voltage source, idk
I had hoped a DSP could do the filtering, obviously need a ADC.
>>why they cannot be made the size of a cell phone
>I think they could if old farts would get into the 21st century already and lern2SMT
Elecraft KX3 has some SMT but not 100%. Discussions on the forum indicated many would hate touch screens but none commented on the alternative with buttons around the periphery as on the panadapter. So yes, I think many are too conservative.

Time for the 4chan rebel?

How come the lower ISM bands are not open for ham use? The ISM bands around here are quiet.

>>1154962
>What do you want to do exactly?
I have had my license for a long, long time but not been active. Work has been brutal but I need to get time again for hobbies and ham is one I am thinking of. A lot of new bands have become available since then so I need to read up, a lot.

A graphical navigable representation would be good.

Where I am now a lot of bands have been open but if we are fairly alone in that respect you cannot use these to contact people abroad. Thus you need to know the allocation home but also abroad.