P2200 Resto - Fools Endeavour

Parts on order, I also ordered (100) KSA992FBU to replace TR101/102 with a matched pair.
BDE still has 2SA1213A, I ordered a bunch to replace all on the board, I just have to make sure to get pin orientation right.
 
I would also check D114-D115, they are double diodes to rectify the 13VAC line (BE) to the VAS
 
Also I was considering replacing the 100uf 10v electrolytic with a film type, just having a little trouble finding a place to mount it... LOL!

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I used a polymer cap here, it works great and should last the life of the amp.
 
I used a Nichicon ES bipolar cap. BTW, there is a tantalum cap in each channel, I would also change it.
 
My digikey order came in, made some progress.
80876C8E-F213-4E21-8866-1BB1D9F828F5.jpeg 79148695-ECA7-4A66-83D8-E5BA413F7ABC.jpeg
While I was working I was double checking some of the components I thought I had tested earlier, well damn, R132 was open replaced with a 22 ohm 1/4 watt, R127 had seen some current and got hot, measures 8k out of circuit, replaced with OEM 10K.

Still waiting BDE to send the 2SC1213 transistors, just checked order status, still not shipped... hmmm.

78CCC7B9-9339-4EB6-9384-72D4353B5223.jpeg Went through my 100 KSA992 to find a pair with high gain closely matched, used this cheapy tester to find the best of the bunch.
Hmmm another lesson forgotten and re-learned, hfe is affected by temperature, damn it. Lol. Letting 20 transistors normalize on the bench then handling one leg with a needle nose to test sorted that issue out. Tested 100 transistors and had to throw away the results, damn it, LOL.
 
Too bad I did not read this thread before you ordered your parts.
Is a 2sc1213 part needed with 500mA Ic in this case? I would think you could use a ksc1845f as a replacement (50mA), you would have to rotate it 180 degrees, since 2sc1213 is BCE
I just looked, ksc1845f is fine for TR105,106, there is a 5mA CCS (D101,D102,TR107,R110), 0.6/120= 5mA, they dissipate nothing.
To match input diff pairs, just measure Vbe ( DMM diode test/ohms mode across B-E) and match to with in 2mV, real simple.
 
Yes sir I am, I have new MJ21193G and MJ21194G on hand just waiting for the other parts to arrive.

I too am repairing a P2200, and along with a number of driver transistors, it has one bad 2SA909. I've checked and replaced all the bad transistors and diodes, basically all from TR109 on up

Can I replace just the 1 2SA909, or do I need to do all 6?

If I do 6 on one side, should I do the other channel also, and what sort of transistor matching is required on the outputs?

BTW, here is my parts list:

Component Original # Mouser Replacement
C101 RR71A101MDN1
C106 EEU-FC1V471
C110 MAL213818221E3
C113 B32529C474J189
C116, C117, C301, C302 EEU-FC1J471
TR101 - 104 2SA872A PNP T092 KSA992FBU
TR105, 106, 108 2SC1213A NPN T092 KSC2383OTA
TR107 2SA810B, V PNP T0220 KSA1220AYS
TR109, 111 2SD381(Z) K, L NPN T0220 KSD526Y
TR110, 113 2SC1213A ,C, D NPN TO92 KSC945CGBU
TR112 2SB536(Z) K, L PNP T0220 KSB596YTU
TR114 2SA673A C, D PNP TO92 (CBE)? KSA708CYTA (ECB)
TR115 2SA682Y on heatsink PNP TO126 MJE253G
TR116 - 118 2SC1586 O, Y NPN T03 MJ21194G
TR119-121 2SA909 O, Y PNP T03 MJ21193G
D101-104, 108, 110-113 1S1555 1N4148
D105 WZ-061 1N5234B
D106, 107, 109 1S1885 UF4004
D114 10DC-1 or 10DC-4 DSTF20150CR
D115 10DC-1R or 10DC-4R DST20150C
 
Can I replace just the 1 2SA909, or do I need to do all 6?
If I do 6 on one side, should I do the other channel also, and what sort of transistor matching is required on the outputs?
if you are replacing with a 2SA909 with the same hfe grading = no
if you are replacing with MJ21193G, then you should use, as complementary pairs
TR116 - 118 2SC1586 O, Y NPN T03 MJ21194G
TR119-121 2SA909 O, Y PNP T03 MJ21193G
You do not need to match above.

TR114 2SA673A C, D PNP TO92 (CBE)? KSA708CYTA (ECB)
2SA673 is ECB according to one datasheet that i have
 
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One other question
I read that TR114 was originally configured CBE, rather than ECB.

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Looking at the picture in the service manual it looks like the center leg is the collector, not the base.
Does the circuit board have the center leg collector, like the picture?
 
if you are replacing with a 2SA909 with the same hfe grading = no
if you are replacing with MJ21193G, then you should use, as complementary pairs
TR116 - 118 2SC1586 O, Y NPN T03 MJ21194G
TR119-121 2SA909 O, Y PNP T03 MJ21193G
You do not need to match above.
Thanks!
 
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