New find on bogus bipolar transistor! (SGSIF461)
Got a few of those and those ran hotter and they blew in PTK169
chassis after hour or so. They was from home-brewed kits that
supplier put together for very good price (about 10 each for kit of:
transistor, three caps (two were wrong types and total correct rebuild
requires four caps, two of them 39uF & 15uF very important), IC is not
fake through because I nut-cracked that.
So got the RCA OEM version and now SMPS's heatsink runs cooler and is
fine.
I saved both blown OEM and fakes SGSIF461 transistors and cracked
them(1). The fake was plated (white) copper plate & had white silicon
splat over the die.
OEM or true ones were unplated copper (shows shiny copper) plate and
bare die assembly cast in black package.
This cost me 2 callbacks on same unit because of this.
Cheers,
Wizard
1. Cracking them, fake transistor was very easy & die intact, I was
surprised. The OEM put up lot of fight before package finally gave way
with loud "CRACK!" and shattered the bare die.
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