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Marantz 2270 Rebuild Help

Just compared my board to rasputin's- looks like I have the diodes correct, but I think my transistors may be backwards, as the lettering on mine is facing the other direction. Is there any way I can tell for sure? If they are backwards, would this have broken them?
 
Did a little research, found out my transistors go E-B-C while my board is E-C-B. I fixed it but still no sound. I'm assuming I broke the transistors by putting them in backwards. gonna get some replacements. hopefully this mistake didn't break anything else..
 
Well, I'm officially stumped. I tested my transistors and they seem to be fine, but I still haven't gotten a single sound from either phono channel. Everything else working great. Any suggestions?
 
I was wrong, if I turn the volume way up theres I tiny bit of fuzzy sound. ame thing for both channels. really need some help..
 
I assume the transistors in question are H705 and H706. What did you use as replacements? KSC1845FTA or 2SC2240BL install exactly like the silk screen on the board indicates.

Tom
 
Are you sure you have them in correctly? I find that it is easier to use replacement parts with the same pin out as the originals rather than bending the leads around.
KSC1845FTA transistors from Mouser work fine.

If it played before you worked on it, then you need to go over your work with a fine toothed comb.
A typical error is to install C713 backwards. This causes R734 (100 Ω 1/4W) to open, removing the power supply to the phono stage. Be sure the positive end of C713 connects to R734. If you had it in backwards use a new cap.

Tom
 
Yes I'm sure. I even re-installed the old transistors to test and the problem still remains. could it be that I damaged part of the curcuit board by having the transistors mis-oriented in the first place?
 
Maybe, who knows?
Take a good clear picture of both sides of the phono amp and post them. Perhaps someone here will spot something.

Tom
 
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