so i've been sitting on a box of parts for like 8 months and finally sat down last weekend and built the NorCal 40A kit i got from a swap meet years ago. the instructions are pretty straightforward but i still managed to wind the toroids wrong the first time, had to recount turns twice before i got it right. just not great at that part.

anyway fired it up this morning and it actually receives, picked up a cw pileup on 7.020 without too much trouble. audio is a little thin but i think thats just the single-supply op-amp stage, might try swapping the LM386 for something with a bit more headroom later. selectivity is obviously nothing special for a DC receiver but for a first build im pretty happy with it. the opposite-sideband rejection is maybe 20-25db which isnt great but its not terrible either.

anyone else still building stuff from old kits they bought and never finished? feels like everyone just buys SDRs now and calls it a day, nothing wrong with that but theres something different about hearing a signal through something you actually built yourself

yeah i have a half-built ugly-style 20m transmitter that's been sitting on my bench since 2019, keeps getting bumped for other things. your post is making me want to go finish it actually.

on the LM386 thing - try putting a 10 ohm resistor and 0.047uf cap in series between pins 7 and ground if you havent already, kills a lot of the motorboating those chips are famous for. also worth trying a 250uf bypass on pin 6 if you're getting thin audio. makes a noticeable difference, at least it did in my version of a simlar circuit. the 386 gets a bad rap but its mostly about how you decouple it.

the toroid winding thing never really gets easier honestly, i still miscount and have to strip them sometimes. just part of the process i guess.

thats cool, DC receivers are underrated for learning how a radio actually works. i built a similar thing a couple years ago when i was studying for my general and it helped me understand mixing and BFOs way better than just reading about it. opposite sideband rejection on those is always kind of a compromise unless you go phasing network or something more complex, but for cw 20-25dB is honestly usable.