Goin crazy on sx-680...

Dwayne Heath

Active Member
I just picked up an sx-680 from a friend ..very cheap..actually..embarrassing lol. Not bad shape either. But my post is regarding the tuner rewind that I am trying to get dun..its a little bit more of a p.i.t.a. then I realized..wow..I would post a photo but every time I take one it's tellin me photo too large?!
 
Try posting as jpg. It's no the physical size, but the number of bytes and the format. I think.....
 
Usually the service manual has an dial string re-stringing diagram.
 
I agree. Just got done reviewing a scan . It was a poor scan.
 
Dial cords are not one of my favorites either. Hang in there , you will eventually get it done.:biggrin:
 
I have a CR-2040 thats going to need to be done.Not looking forward to it.At least the Yamaha manual is pretty good.
 
The double slipknot at each end is the worst. I just repaired a cracked drum on a 750 a couple weeks ago and restrung it from scratch. About one of those a year is plenty.

Hopefully this is a little clearer:

SX-680_780DialCordStringing.gif
 
If you are having to restring, you may want to fix the pully shaft, as it is usually loose where it connects to the small pot metal gear. If it is loose it is pretty easy to pull it out and have the gear and washer drop out when doing the restringing.

Understand that when you remove the shaft, the gear drops out along with the stop washer. I usually remove the 2 small screws that hold the small pot metal frame to the tuning capacitor. This way you can work on it easier. I used to try crazy glue, but it always dried before I set it properly. So now I distort the end of the shaft where it goes into that pot metal gear. I use a heavy pair of Dikes and just put 2 small crimps onto the end 1/8 inch apart. Then you can put the washer in place and push the shaft into the gear . Tap it in and it should hold fine. You then need to reset the spring loaded gears so the assembly doesnt have "gear slop"

But if the shaft doesnt seem that loose, you may not want to tackle it, just be careful to not pull it out on the restringing. You may want to see if it may have come out before and somebody else put it back in. Easy way to see is check that the spring loaded gears are still spring loaded.

The procedure is hard to explain in words. I may put a little tutorial together to explain how to do this as well as show pictures.
 
For what it's worth and since the 680 is pretty much the same as the 690. I recently got a SX-690 that was toasting speakers and had rail voltage on both outputs, turned out R410 which feeds the power amp circuitry was open which was causing the offset, might wanna check and probably upgrade that resistor to a 1/2 watt as a precaution while you're in there.
 
For what it's worth and since the 680 is pretty much the same as the 690. I recently got a SX-690 that was toasting speakers and had rail voltage on both outputs, turned out R410 which feeds the power amp circuitry was open which was causing the offset, might wanna check and probably upgrade that resistor to a 1/2 watt as a precaution while you're in there.
Thank you
 
If you are having to restring, you may want to fix the pully shaft, as it is usually loose where it connects to the small pot metal gear. If it is loose it is pretty easy to pull it out and have the gear and washer drop out when doing the restringing.

Understand that when you remove the shaft, the gear drops out along with the stop washer. I usually remove the 2 small screws that hold the small pot metal frame to the tuning capacitor. This way you can work on it easier. I used to try crazy glue, but it always dried before I set it properly. So now I distort the end of the shaft where it goes into that pot metal gear. I use a heavy pair of Dikes and just put 2 small crimps onto the end 1/8 inch apart. Then you can put the washer in place and push the shaft into the gear . Tap it in and it should hold fine. You then need to reset the spring loaded gears so the assembly doesnt have "gear slop"

But if the shaft doesnt seem that loose, you may not want to tackle it, just be careful to not pull it out on the restringing. You may want to see if it may have come out before and somebody else put it back in. Easy way to see is check that the spring loaded gears are still spring loaded.

The procedure is hard to explain in words. I may put a little tutorial together to explain how to do this as well as show pictures.
That's Exactly what I am struggling with now..the little gear and washer fell out and I am tryin to put shaft back in straight up and down like it says to do..
 
My stupid ass is having trouble remembering or seeing the order of the shaft assembly..does the washer go on after the gear ?
 
For what it's worth and since the 680 is pretty much the same as the 690. I recently got a SX-690 that was toasting speakers and had rail voltage on both outputs, turned out R410 which feeds the power amp circuitry was open which was causing the offset, might wanna check and probably upgrade that resistor to a 1/2 watt as a precaution while you're in there.

same problem w/ me my SX680 toasting my speaker replace STK but nothing fix
 
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