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SX-1010 won't Power On...

you should save the legs off the capacitors that you trim off after installing them, they make excellent trace repair wire. i would follow the trace up to the next leg (D4) along the route and solder to it then to the trannie (base of Q8) and from there down (R24) then form the wire to conform to the trace and put a drop of glue on it..voila
 
I agree, plus if you saved the foil that came off, you could get it back in place and use the component leads as splints to secure it in place. The splints would have to be continuous from the previously named component junctions - all the green comes off and the foil is soldered the entire route along the extra component lead....

I will be in and mostly out until the end of the week, at which time hopefully all the ducks that are nibbling me to death will have been converted to tasty dinners.
 
I have been meaning to share something that was bothering me, a common component on both PA Boards, the in D6 (between pins 11 and 13) The right PA Board had a completely different diode than the left one which seems to be original. Also, while I was working on the right PA Board, the 'different' diode that looks unoriginal came off (one of the leads broke off) without applying any force, as if it was barely hanging on. I installed a 512-1n4004 in its stead referring to http://www.audiokarma.org/forums/showpost.php?p=2420175&postcount=492 at which you confirmed D1 through D7 being 512-1n4004. I hope I have not done something foolish. Here are the shots of the diodes in question:


The Unoriginal Diode (Front Shot)
DSC08555.jpg


The Unoriginal Diode (Back Shot)
DSC08552.jpg


Replacement Diode
DSC08556.jpg


Untouched (Original) Diode
DSC08557.jpg
 
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After going through the parts list in the Service Manual (Page 51), I realized what a terrible mistake I have made. The D6 in the PA Boards are STV-3H Varistors. Instead, I installed a 512-1n4004 rectifier referring to D6 on Power Supply Board. What a HUGE HUGE mistake. I will remove it right away though I don't think I have a replacement STV-3H for the Right PA Board.
 
I have been trying to whack my head to figure this out. Post #543 shows you circled what you replaced which is D8. While you didn't do anything wrong but would be better if you use UF4004 which is ultrafast diode for D7 and D8. As for D6, yes it is a horseshoe varistor which is mounted on the large heatsink. I am trying to figure out how did you make that mistake putting a 1n4004 doide? Even with the diode you put it in(the right polarity), it shouldn't blow fuse. It should at least not sound good for being ~1/3 voltage drop of the original causing underbiasing. What happened to your original STV-3H?
 
There wasn't an original STV to begin with, that is why I posted the 4 pictures above. The first 2 pictures show what came out of where the original STV should have been.
 
Okay, your 2 pics show D8 not D6. That is what you're referring to RIGHT? I want to make sure we're on the same page.
 
Hmm, I thought that was D6, the print is too small on the manual. But it probably IS D8, you're right. Yes, I just checked the Manual again (Normal Resolution this time which shows it much more clearly) itindeed is D8.
 
I saw the term "blow fuse".....

I don't THINK that is happening, just checking....

Everything else is well in hand - D.E.K good work on the trace repair....

btw: (my style would be to make them shorter so they run directly over the damaged foils, thus not introducing any crosstalk considerations, but things should be ok here....)
 
Thanks Mark. She's blowing a fuse though, as soon as I power up the unit. My amateur guess on the culprits:

1-) The 'poor' soldering job of the broken wire onto the pin (refer to attached picture). I will remove the rest of the wrapped wire off from the pin, clean the pin and try to do better.

2-) The pressure put on the 'red' trace repair by the back plate (the black plate on which the PA Board is screwed) causing the exposed un-insulated end of the wire to bridge to the nearest trace, causing a short. I will take your advice and shorten the bridges, making them straighter directly along the traces.

3-) I installed one or more of the replacement units incorrectly. I might have gotten careless and confused NPN and PNP somehow which I really doubt because I powered up the unit fine after replacing all the Q's and I even got faint sound on one channel in FM mode. Regardless, I will go through the 'Q' designations which I replaced all 12 of.

4-) I broke one or more of the wiring or even the STV-3H wires. I will go through all the wiring.

5-) Worst case scenario, one or more of the output transistors is blown...

DSC08556-1.jpg
 
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Hi again Mark. I renewed the bridges, I removed the remaining wire that was wrapped on Pin #15 and soldered the broken wire directly onto Pin #15. I also replaced the 512-1n4004 at D8 with a 512-UF4004. Checked all wires on the PA Board and everything seems okay. I powered up the unit with the DBT and the bulb did NOT go dim. There is a serious issue somewhere. I am thinking it is Pin #15. Before that wire broke, the unit powered up just fine. I am going to take out the power transistor that is related to Pin #15 and take some readings to make sure it is okay. If the unit was somehow powered up (I'm not sure) with that cable out of place, the output transistor might have blown. Well, at least that is all I CAN do while you're not around.

PioneerSX-1010RightPABoardBridge-1.jpg


PioneerSX-1010RightPABoardBridges00.jpg


PioneerSX-1010RightPABoardPin150-1.jpg


PioneerSX-1010RightPABoardPin150000.jpg
 
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Pin 15 is the emitter of a power output transistor.

Yes, pull it.

D8 was replaced by two uf-4004's - not a really big deal.... the other three corresponding locations also get two uf-4004's apiece. This was something that reflects back on old and somewhat newer production models.

It started with a single diode, then later they decided to use a bigger voltage drop, and the stv-3 diodes were convenient, as they didn't have to add holes on the board for the extra diodes for voltage drops.
 
Good job on the jumpers. Wire breaking off pin 15 sure could be bad news. Don't be discouraged though. I blown stuff before. I'm sure Mark blew up something before too. :D That's how we learn, from our mistakes. You are doing well Des.
 
The NPN that is related to Pin #15 is blown. Good thing I have one of the original NPN's (2SC1079) reading at about 0.497 so I decided to try it on, with the DBT of course. The rest of the output transistors on either heatsink are fine. Now what happened was, the DBT went dim for about 0.5-1 seconds then back to normal, fully bright. After it went back to normal, the bulb immediately started flickering continuously, non-stop. While on and bulb flickering, there are absolutely no lights coming on in the receiver or any signs of life. I don't know what to make of this except that there is a problem, possibly voltage related, hence fatal. I am not trying the unit without further assistance and suggestions. I am not worried if a 6.3A fuse or two are blown but I really won't be impressed if the only NPN output transistor I have IS.

P.S: Congratulations on winning the "Member of the Year" award.
 
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The dim bulb tester should be bright for a second or two, then dim down and stay dimmed. Bright means problems.

What have you done so far? I have to catch up, other things were in my mind for 2 weeks or so.
 
Things done so far:

1-) Repaired the traces (Page 37, Post #553)
2-) Replaced the diode at D8 with a 512-UF4004
3-) The wires on Pin #14 & 15 broke so I soldered them back onto the pins
4-) The output transistor related to Pin #15 was blown so I replaced it with the original good 2SC1079 I had

That's it...
 
Weren't you swapping out transistors, when the need to fix the trace became apparent?

That counts (swapping) as "done so far".
 
If by 'swapping out' you're referring to firing up the unit with 2 output transistors on each heat sink, I haven't done that yet. That is next. Maybe after that, firing up the unit with NO output transistors and taking readings of each sockets maybe? With the BIAS turned down way low of course.
 
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