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Sansui 7070 no bias voltage - transistors?

TMaster

TMaster

Transistors for teeth? They do have roots...
So I rebuilt my 7070, put it on the dim bulb, and it was dim, no shorts. I have no amperage on posts 05,06 / 05,07 when trying to adjust the bias ma. Also the sound is very faint / weak in both channels even with the volume up to max, and when the relay kicks in there is a pop sound even at low or no volume, its not smooth. I am wondering if the transistors I picked are not the best replacements. I did not replace the Driver transistors or the 899 and 1904 flat transistors because the receiver was working before I started the re-cap / rebuild. The KSC2383 has a 6V emitter voltage. I am debating on putting the 2SC984's back in. haha

F-2624 Amp board:
TR01 - 2SC1708 to KSC1845
TR02 - 2SC1708 to KSC1845
TR03 - 2SC1708 to KSC1845
TR04 - 2SC1708 to KSC1845
TR15 - 2SC945 to KSC2383
TR16 - 2SC945 to KSC2383
TR17 - 2SA733 to KSA992
TR18 - 2SA733 to KSA992
TR09 - 2SC984 to KSC2383
TR10 - 2SC984 to KSC2383

Thanks!
 
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It turns out I placed the KSC2383 wrong because the board layout was EBC instead of ECB for TR09 and TR10.

I swapped them with a couple new ones and put them in correct and didn't fix the problem. I am guessing something else is damaged, will have to pull the board and check everything. DOH!!!
 
As Robin said above, you should put the original transistors back, if the unit was working prior to this. None of those transistors used on that driver board are known as "problem" transistors, so I see no need to replace them. Replacing things that don't need to be replaced has gotten you into this current situation.
 
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