Hey guys, so as many of you have been aware I have been working on a 4300 (or two) for the last few months. Its been and adventure and a learning experience, and I am extremely grateful for the wonderful help I have received from various forum members. I figured Id keep making new rebuild threads when I get things o that I am not a "taker" from this site, but also a giver. Without the information found here, none of my work would even be possible.
This 4300 was given to me for a partial restoration/tune-up, and I had no clue what mess I was originally getting into, should have just immediately returned it to the guy, you can see my original thread for the details there. The first one had a ton of questionable work and after fiddling for a few weeks, and one small tragedy, I had relegated it to a parts unit and managed to acquire another in a moderately less molested state. I'm actually taking a pretty huge loss on this servicing money-wise, so some things (like the filter caps, dolby board and tuner) are being left out to save me a bit.
The original one wound up befalling a tragedy, at my fault, ultimately costing me around $400 and a whole lot of time/parts, since after breaking one of the pushbutton boards and several buttons the original unit was no longer worth the time or the effort to repair (in addition to many other issues it already had). Essentially split the price of the new one, and am doing a partial rebuild and addressing areas of concern/potential reliability issues.
So far I've gone and done the main amp boards, preamp and tone board, and the PSU. Going to do the phono board, Vari-Matrix and Phase inverter and the call it done, for my sanity and time's sake.
So far I noticed both of the amps had work done on the main amp boards, I used the two boards that were closest to original and didnt show signs of abuse by extremely bad servicing, had to toss both amp boards from the replacement amp as one was using the wrong driver transistors (probably fine), one had the D357 transistor replaced and there were a few other small issues here and there. The other amp just had most of its small-signal transistors in the amp board replaced, looking the replacements up the proper ones were used, so I decided to use those two amp boards.
Both amps also had work done on the PE01 board, the first one just had random components popped in (no joke found transistors in places they shouldnt be) and the 2nd one actually had proper replacements for a few.
Original amp even had mismatched filter caps...
Ill be updating this thread as I get to it, there's a lot to post...
This 4300 was given to me for a partial restoration/tune-up, and I had no clue what mess I was originally getting into, should have just immediately returned it to the guy, you can see my original thread for the details there. The first one had a ton of questionable work and after fiddling for a few weeks, and one small tragedy, I had relegated it to a parts unit and managed to acquire another in a moderately less molested state. I'm actually taking a pretty huge loss on this servicing money-wise, so some things (like the filter caps, dolby board and tuner) are being left out to save me a bit.
The original one wound up befalling a tragedy, at my fault, ultimately costing me around $400 and a whole lot of time/parts, since after breaking one of the pushbutton boards and several buttons the original unit was no longer worth the time or the effort to repair (in addition to many other issues it already had). Essentially split the price of the new one, and am doing a partial rebuild and addressing areas of concern/potential reliability issues.
So far I've gone and done the main amp boards, preamp and tone board, and the PSU. Going to do the phono board, Vari-Matrix and Phase inverter and the call it done, for my sanity and time's sake.
So far I noticed both of the amps had work done on the main amp boards, I used the two boards that were closest to original and didnt show signs of abuse by extremely bad servicing, had to toss both amp boards from the replacement amp as one was using the wrong driver transistors (probably fine), one had the D357 transistor replaced and there were a few other small issues here and there. The other amp just had most of its small-signal transistors in the amp board replaced, looking the replacements up the proper ones were used, so I decided to use those two amp boards.
Both amps also had work done on the PE01 board, the first one just had random components popped in (no joke found transistors in places they shouldnt be) and the 2nd one actually had proper replacements for a few.
Original amp even had mismatched filter caps...
Ill be updating this thread as I get to it, there's a lot to post...
