That is a good question. On all the transistors, I desoldered them from the board and popped them into a cheap tester, which I think runs a couple of different tests and reports the highest value of hFE it finds. At this point there are so many loose parts that it's probably easier to find the bad part by breadboarding the whole thing.
thanks for the heads up, turns out ours is the "MP1-L3 a.k.a. "The Big Daddy"" lol. I've seen even weirder OSA stuff that never got released, as well.
It's soft like silicone sealant, so you just carefully scrape it away.
That’s great to know, thanks a ton
Any tips on removing the back panel without breaking it? (If doable)
Exactly. I used a blade to slice away a lot of it, sometimes like carving up a cake. Then poked & scraped a lot of the tiny bits. It does take a long time.
I've built this one. Same circuit with two series diodes to replace the stabistor. Works great. Behaves a bit differently than their CA-0252 and both are nice. Build em both and see which you like better.
