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Those numbers look right to me. MP39s Ive tested have had leakages close to 0, they are low noise parts. And leakage is supposed to me in uA, not mA, right?

All same markings 400-700 hfe (most ~500).

Ive gotten many transistors sold as kt3102em from Ukraine that arrived and were the color dot ones (white/green?) Its probably just a different factory's marking. They test in the same ranges and sound the same to my ears as kt3102EMs marked with writing.

Im not familiar with the design, but I think the problems you are having could be related to the following:

I dont think using the case as the antenna is the best idea, the floor is closer than you are, so its going to be a nightmare to tune.
Most theremin designs need a good connection to an earth ground to work correctly, Im not sure how that is happening here.

To oversimplify, basically you have two AM radio transmitters, and your capacitance to the antenna is the tuning cap for one of them. The two signals are subtracted from each other and produce a sine wave in the audible range.

Yeah, I just drill the hole a size small, then file it out until I can jam it in. I havent had one fall out yet, and Im rough with stuff.

Also, sometimes my peak dca gives weird readings for fv on germanium diodes, giving much higher fv than expected (like some models of ge diodes with fvs of .56). When reading with a multimeter, i get expected values (such as .26 for the same diode). Id use a multimeter for sorting.

If its germanium, your multimeter hfe setting is not going to give accurate readings, it likely does not account for leakage. Theres instructions on geofex.com under "selecting transistors for a gain and leakage for a  fuzz face clone" on how to measure leakage.

Some of the mods to the original he makes I dont agree with. Using mpsa18s for instance makes it not cut off all the way, which is sort of the point of the original. Take the original schematic and his and breadboard both.

the vox repeat percusion on moosapatamus. Any project with a rate or speed pot could probably be modded in the same way.

Ludwig phase ii on geofex.

Does anyone know of a good, comparatively safe etchant for steel enclosures? Ive been using copper sulphate, which is slow, and Im finding it hard to get fine detail, and anything thats not lacquer/or nail polish as a resist, breaks down quickly. Is there anything better that doesnt require a hood/full respirator?

Vox repeat percusion.

Thanks, FW it is.

Thanks for the quick response. Is theres any reason to pay the few extra bucks, for the 105C rated caps over the 85C? Such as, will they last longer? Or at 30C max operating temp will it just not matter?

Ive used up my bag of cheap tayda 100uf caps ive been using, so I need to buy another hundred or three, does anyone have any recommendations/favorites? Mouser is making me dizzy.

For this application, low esr doesnt matter, no? I dont often build 1590a, so size doesnt matter. I just dont want to have to worry about their reliability, or failing in 8-10 years.