Recent content by jahmadeus

Decided to proceed with the 50 degree access that I had gained from desoldering that one (2 conductor) blue wire. Used a mirror and flashlight to inspect solder joints, found a couple cracked joints and reflowed them. As for the caps, just as I thought, every blue Sanyo cap was gone (off value...

This is essentially where I am at now. If I need to replace components like this, it would not be the end of the world. However, a close inspection of the existing joints and my rework, will be difficult on the half of the board not lifted up. Again, not the worst thing that can happen. I worry...

The wires that appear to tether it down on my particular unit are the ones that attach to the underside of the tuner board (and connect to the underside of the tuning capacitor section). It seems like these are the only connections keeping me from easy access. I have probably overlooked some...

Yes this has been my approach thus far; avoid stressing the wirewrap posts in any way unless absolutely needed. This is my primary reason for posting here, to get some feedback on what others have found to be the most efficient, least invasive method. Definitely. For me, part of the joy and...

It is good to know that this can be accomplished by selecting a few specifc posts to desolder, not having to desolder an entire row of posts is ideal! I hadn't thought to do this! I will keep this in mind when I go to do the deed. Photos and notes/diagrams are a must! And I totally...

This is typically my attitude, best not mess with anything tuner related if you don't absolutely have to. I plan on being very light handed in working on the tuner section as I do not want to mess with the alignment. Mainly want to change the blue sanyo caps which so far in the amp have been...

Hello all, I am finishing up a rebuild of my SX-1010 and only have the tuner board left to work on. I have noticed that it is tethered down by its wire wrap connections on nearly every side. I have had success with desoldering select wirewrap posts from the other boards to gain access. However...

I had a few different types laying around as I work for a shop that has a pretty huge stock of NOS parts. Some that were purchased recently (slightly smaller package, marked as 'F' class) that tested lower for hfe (350 - 450) and some older ones (marked as 'E' class) that tested closer to 600...

The plot thickens... So I returned my focus to the three transistors in the bias network (Q5,Q6,Q7). I decided to swap Q7 with one from the working channel. The problematic channel now has a normal bias range and the previous working channel has the low bias. However this is weird as I already...

Yes indeed. The problem is im running out of things to check. I went ahead and shotgunned all the semiconductors in the protector circuit and the passives all seem to read normal. Maybe its a resistor that is opening up under load? The weird thing is that no matter where i probe for voltage...

I initially suspected those. They seemed to ohm fine out of circuit and they all decrease in ohms when heated up at the same rate as the ones from the healthy channel.

I suspect this is the case but so far everything checked tests fine against the schematic/other channel. I swapped out Q5, Q6 and Q7 to see if that would make a difference and it did not. I have not tested (out of circuit) many of the passive devices in the protector circuit, I think I might...

I am currently working on a Sansui B-77 that has been giving me a lot of grief. When I received the amp, the outputs on the left channel were shorted and a few nearby resistors (kR22, kR24, kR25, kR29) had smoked. One of the drivers (kQ9) had been replaced with a substitute. Everything else...

Yeah, I will definitely be going through all the boards and giving them a complete once over. Recapping is my starting point but it seems many people I talk to that have experience with these units say the transistors are bound to fail. I have repaired a few dozen of these era pioneers (no...

Yes I have seen your thread, very nice work. I agree with your methodology on cleaning the controls. I do repair professionally and have had close to 30 or so of this style of pioneer on my bench (although funny enough, not one 1010... yet) and have learned that these units can require more...