/diy/ - Do It Yourself

>>1663657
>The audio transformers I see aren't exactly too expensive, but I suspect they'd be more prone to noise
in a metal box, probably not enough to matter. it's a question of how you want your sound colored
>48V rails
just put some nice caps in there. dc level is mostly irrelevant to the output anyway
>diff amp circuit
I probably wouldn't, only because I can't be sure how long a cable I might like to use with it someday
>controller on secondary side
much more effort than it's worth. most of the controller's concerns are primary-side, e.g. switch current, switch temperature, line voltage, and that's before you consider the bootstrapping problem of getting enough energy over to the secondary to bring the MCU up. could indeed be worth it if you're doing some quad-pumped arc welder kind of thing
>switching patterns
the weirder the pattern, the more bandwidth needs to be covered by the input filter needs to be to prevent using your house wiring as a broadcast antenna. a touch of spread spectrum could be welcome
>rewind
hope you have room on the bobbin. neatness counts~
you might find transformers for closer to 50 cents each if you shop a little harder. as long as the operating frequency is about the same or lower, you're probably in good shape to substitute. worst case is reduced output current due to core saturation, switch current limit, and/or thermal shutdown

>>1663694
>no electret bias
that doesn't look quite right

>>1663688
>lower voltage wall supply and boost it
this is probably the correct answer. either LM5001 or LM5002 are probably the correct IC, but expensive from ali, even worse from Digi-Key, and Jaycar sends Pic related to your house to collect the price of one