Pioneer SA-8100: Protection (yes, again)

I wish someone would carry 3503 with E or F gain designators. The new TTC004 (1.5W, 1.5A, hfe 140-280) looks like a nice sub, if Digi-Key or Mouser would ever bother to stock them.
.....
Mouser seems listening to you, they have TTC004B on order. The TTA004B they have in stock :thumbsup:
 
This one has the top-mount flange. I may just go with 653-MY4-DC24 and use the flange mount adapter with mod. Thanks guys.

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Does anyone know the size of the plastic circuit board locking supports used in the SA-8100? A few of those holding the protection board to the chassis broke when I tried to release them. I'm away, otherwise I would just measure them myself.
 
^^^ It looks like you're stuck with the MY4 top flange relay.
Does anyone know the size of the plastic circuit board locking supports used in the SA-8100? A few of those holding the protection board to the chassis broke when I tried to release them. I'm away, otherwise I would just measure them myself.
1/2" threaded nylon spacers work well.
 
Despite my best efforts to not leave anything out of my Mouser order... I left something out. Two somethings to be precise: Replacement caps for C1 and C2 on the AWM027 D protection board. There are two of those light blue Sanyos in there (0.22uF/10V). I assume Wima film caps would be the recommended replacement. Since I'm placing another order anyway, are any of the transistors on this board more likely than others to be problematic?
 
.22uF film caps are the best replacement for the Sanyo tantalum caps.
If Q1, 2 are 2SC869, I would replace them with KSC1845.
 
.22uF film caps are the best replacement for the Sanyo tantalum caps.
If Q1, 2 are 2SC869, I would replace them with KSC1845.

I'll check Q1 and Q2. Thanks tarior.

P.S. I believe those Sanyos are 'lytics, though 0.22uF films are still the way to go.
 
Man, what an absolute pain to access the solder side of the power supply board. Unless I'm missing something (very possible), I'm not seeing any way around desoldering a number of wire wrap pins. @markthefixer ?
 
I haven't worked on that particular amp, but usually you can work all of the wires out of their holders on the bottom side and gain enough slack to access the bottoms of the boards.
 
This cap on my picture jumped off its seal at first power up of my already defective amp. I remember it has maximum voltage on it or more (50 volts or so) which is no problem when new, but.....
Even if not recapping I would replace that one, regardless of what other porblems exist. (of course, AFTER having experienced this).

As stated above taking out the wirewrap pins is no big deal and it makes working on parts and cleaning the board easier when having it on the bench.
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Just make sure the square holes are clean (solder or flux) before trying to reinsert the square pins, and the square of the pin is aligned to the square of the hole.
Otherwise the pin will wobble OR TEAR THE PAD OFF THE BOARD!!!

And of course get the right wire back in the right place. Take pictures and CHECK them against the visual colors, Label the wires if any doubt as to the pin number - you WILL thank yourself later.
 
Man, what an absolute pain to access the solder side of the power supply board. Unless I'm missing something (very possible), I'm not seeing any way around desoldering a number of wire wrap pins. @markthefixer ?
It is very tight, but I was able to get under there with the soldering iron without removing any wires/pins when I recapped the power supply on my 8100. It is by far the most difficult board to do in that amp; although the switch board is also very tight, and I ended up not changing 2 or 4 caps on that board because I just could not get in there without removing a bunch of wires. On the power supply, as others have said, remove the tightest wires from their clips to give some slack. You should be able to lift up the board enough to ge the soldering iron in there and remove all the caps. I did the work by myself, but if you could have a third hand to hold the board while you use the soldering iron in one hand with the other hand on the cap to pull it out, that would be helpful.
 
After much contorting (but no desoldering of the pins), I believe I have the power supply board accessible enough.

Question regarding a difference between what's on my board--AWR 030 A--and what I see in the cap list: At C16, my board has a 220uF/50V, whereas the cap list (and the SM I'm looking at) specifies 330uF/35V. Is this just a difference in board versions? Of course, I ordered a 330uF/35V before checking the board....
 
Are you sure you are looking at C16 and not C17? C17 is 220µF/50V according to the service manual, but C16 is 330µF/35V.
 
I'd guess you have a later revision (service manual is AWR-030-0), which seems to be the case since your board is marked AWR-030-A. When recapping my 8100 I did notice that a number of the boards were redesigned in later revisions and thus did not match up with the service manual. A good example is the protection board. I have AWM-027-A, which matches the service manual, but it was redesigned later, and the layout is not the same and does not have the same components. I recommend making sure each of your boards matches up with the service manual board layouts/parts list.

I am not expert enough to agree or disagree with whether you can sub a 330µF/35V cap for a 220µF/50V on that board, though the lower voltage of the 330 cap from the 50V cap you have in there would raise a red flag for me in addition to the significant difference in capacitance. My understanding is you can go higher in voltage with replacement caps, but not lower, and you need to match capacitance, so that is what I follow when doing recaps.
 
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