Pioneer SA 9100 (910) Help restoring

[speks]

Hi, so i have this pioneer sa 910 (The japanese version), and it needs a full restoration, and i dont know where to start, anyone help is appreciated.

When i firts got it, it turn on but the protection light it stays on and the relay does not click, i recap and change all the transistors on the protection circuit awm 025A, and after that i turn it in on, the protection light when off when the relay click after 2 seconds, after a few mores seconds, the relay clicks off and the protection light come on againg, and is stays like that.

The thing is, that i was trying to take some measures from all the pins on the board, i realice that pin 3 is the only one that has solder in adition to the wire twisting, and while the amp was on, I rub the pin with the miltimeter probe, some sparks come out and the relay click on, and from that moment, when i turn the amp on, the protection light comes on for 2 seconds, then the relay click and the light goes off, and it stays like that.

Did i damage somenthing else? What should i look for?

This are the readings afters the sparks.
Pin 1 -9.8v
Pin 2 -10mv
Pin 3 -30v
Pin 4 grn
Pin 5 -10.5v
Pin 6 -13v
Pin 7 -25v
Pin 8 -27v
Pin 9 7.7v
Pin 10 30v
Pin 11 32v
Pin 12 all over de place

Thanks again for the help.

 

[larryderouin]

Solid core wire used by PIONEER gets brittle over time and doesn't like being handled, so it can/will break at the most inopportune times and places. It's possible that the wire broke at the beginning of the Pin 3 wrap, and rather than removing the original wrap, then wrapping by hand and soldering it all, the previous guy just ran a wrap or 2 by hand over the old wrap and tack soldered it on. Since that time the solder joint cracked (what's called a cold joint) and went intermittent. By you manipulating the pin with your probe with the power on, it sparked when it made contact and literally spot welded the wire on just enough to make contact. And it's now running.

Someone was screwing around on Pin 3. Only one wire is supposed to be there. The YELLOW WIRE (skinny one) is original. Trace it back to it's origin @ pin 12 on the amplifier board (AWH-023). Then trace the FAT wire back to other end. If it goes to pin 12, one of them is broken. Bet's are it's the smaller solid core wire. And it was bridged with some 18 or 16ga stranded, not removing the now broken original. See if you can find about 5 ft of 20ga solid core wire in Yellow. Then re wire from pin 12 on the Amp (AWH-023) back to Pin 3 on the Protection board, following the original path. Make bend at least over your thumb so they aren't sharp. give it a couple turns on the pins and solder.


Japanese version? 100v? Are you using a step down transformer? Location in your profile helps a lot with esoteric stuff like wall voltages, etc.

That skyblue Sanyo capacitor in the lower right hand corner of the AWM-025 board?!?! Replace it NOW. Same Value, voltage. Add a 1n4004 across Pins 9 and 10 (cathode side (striped end) to pin 10). The AWM-025 board was also used in the SX-737 altho it's a "C" Suffix. The Caps and the transistors are the same.

Pin 12 "all over de place" Bets are your Voltmeter was set to DC Volts, Right?! As there is no manuals for the 910, best to use it's North American counterpart the SA9100. Pin 12 is an AC VOLTAGE. This comes off the Pilot lamp circuit.

 

[speks]

Thanks Larry for the help.

I remove the old solder from pin 3, and resolder with new one.

After looking for other protection boards, i realize that other boards are the same, with solder on pin 3, and two yellow cables wrapped around, so that makes me believe that this os how is supposed to be.

One yellow cable goes to pin 12 on the AWH 23, and the other one goes directly to de relay pin 10.

Yes i do have the 100v ac, i live in Mexico which is 110v and i use a step dow transformer that gives me 100v steady, and can handle 1,500W.

Since the relay is pulling in, what bord should i do next?

Thanks for the help