On Sun, Feb 2, 2025 at 02:39 PM, Karin Johnson wrote:
ronix curve tracers, would be willing to run a series of tests comparing the
so called replacements against the original types???? I would send the batch
of transistors to you to evaluate. That would at least give me some hope that
I can use somewhat original parts to facilitate the repair. I have spoken to a
person who has been down this road before and they have indicated that even if
I were to use the knock of type of transistor, the amplifier would probably
work for a few months and probable die the same type of d
I am in New York and have a 576. Can you share your detailed test plan that you would be looking for the person to execute on these devices? Maybe you want someone with more than a curve tracer, to measure transition frequency, etc?
And... I know you don't want this answer but:
I wouldn't spend any time on this unless the MT-220 devices you were looking to swap in were pulled out of a known working amp yourself (they were used in a lot of BPC so maybe you can find a cheap amp to salvage them from?).
A friend of mine sells nice MT-220 to TO-3P adapters on eBay for $2 each. (other style here: ) - if this was my amp I'd feel much more comfortable using those and buying genuine semiconductors from digikey/mouser.
