Speaker Selector Switch Pioneer A-676 fixable?

Have not looked at the schematic so maybe got it wrong. From the posts above it looks like one of those designs where the relay will only engague
once the spkr set is selected. If the spkr selector is not working then don't blame the relay. Forget the relay(s) for the time being and fix/clean the spkr selector,
check connected wires/joints...
Okay. Everything as I can see if clean for sure and no cracks on the boards. The switch is gone - out - kaput, I have to scratch the trace a bit as the 'hole trace' in 3 slots came out - (rookie solder - but did not burn the board per se just those little copper holes came out) 2/3 conduct, one does not so I will try to carefully scratch the coating and jumper wire this other switch (commons are off from original - so I have no choice) and plug the 5 wire ribbon cable back in and fire it up. I am pretty sure it may not be the relays as you mentioned.

The trick is I have the original switch and I am trying to study the traces on the switches' PCB and going to the schematic to find the 'rest or OFF' position, then hooking the jumpers to Speaker A and so forth. And try to see if I got the positions right.

I cannot find an original style switch, so I was going to just carefully use short 22awg wire and put them through the 'through holes' of the switches' PCB, then click through each position to test. I see RY901 is for Speaker A side and RY902 is right.

I tell ya' this hobby is challenging but somewhat fun (hoping to not do any more rookie boo boo's)! LOL

Thanks for your help I am in the shed tomorrow trying to doctor up this switch!
 
Going to try to wire in this switch, it is the only one I got that is close to the original. I seek help with knowing the right position with respect to: Off/A/B/A+B. I posted photos with this message of the original switch (3 commons - are missing the traces and one needs to be 'scratched' to get in contact with that leg of the circuit on the speaker selection board) the other two conduct.

The wrong ordered switch has the commons closer to the middle - thus, why I have no choice to use jumper wires and solder them to the through holes and with the right connection hope it will work.

The switch PCB is not connected as you can see but I was wondering if I just try one position to see if the relays will click back on would that be okay?

When you guys test amps for voltage readings, do you put the black probe on the chassis and just use the red to see the totals? I do not think I have to do this as the problem was the switch.

I am reading 1.08K ohms on each relay coil (2 are A and B, 3rd is headphones - I was told).

DBT shows no shorts, fuses are fine, power light on, etc, I am hoping I am getting close to fixing this but want to be safe. Can someone help out with the positions or can I do a trial and error but hope it will not hurt anything if I end up having the "Off" position in the A or B or A+B!



A bit complex to find the right combo...my first fix - the schematics are cut off and are a bit tough to follow the solid lines over to the next page when you scroll down...DSCF6133.JPG DSCF6134.JPG DSCF6135.JPG DSCF6136.JPG DSCF6137.JPG DSCF6138.JPG
 

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Relay(s) do not click.

Quoting what someone mentioned from another post: "looks like time to test the dc voltage at the relay contacts that come from the output .not the speaker side..." Would like to know what readings should be and am' I putting the meter on DC voltage "while the amp is on"?

> Switch is back in (but knew this is not the fix for the relay issue)

> Fuses are fine, tried swapping with new ones same (no blown)

> No DC voltage at the terminals (but I just learned that there would be nothing if the relays do not complete the circuit to terminals)

> I tried learning where you take the ohmmeter and test those big white 0.22 resistors and just below are two transistors (SCR's?) one is green (each channel) and one is black. I get readings on everything even by reversing the leads (yes I am lost to know the correct way to put the red and black probes)...although the white resistors when reversing the leads do not give a reading...so I think that might be normal.

I admit this is a tough curve but I am willing to learn if someone is able to offer detailed help with pinpointing where the output stage area(s) I should probe and if I am using DCV and turning on the amp or DC Ohms (power off)?

Power Light comes on - I tried tapping the relays two are Omron and one is DEC.

Again, this issue was caused by turning between Off-A-B-A/B to work in deoxit with the power on (should have been off) so something 'retired' LOL and I think it may be the relays? If they are the relays, do I try to open and fix (which I think you cannot just clean them) or other (replace - good luck right!!).
 
Update:

Tested all 3 relays with 15 VDC 2A power supply (all I got) and I touched pins that showed a coil (basically the two single pins - not the 4 pins at the other end).

So, is this then 'no power getting to the relays' where the issue is a capacitor that went in that side of the circuit? I tested all the resistors on the circuit board that houses the relays and speaker terminals and they were good...so wondering the only component type left was the capacitors. I did use an ohm meter and got readings on all those caps I know this not accurate but none showed being open...?!!

OR

Does anyone know what the likely culprit is with all this deduced testing? LOL

Thanks in advance!
 
Have not looked at the schematic so maybe got it wrong. From the posts above it looks like one of those designs where the relay will only engague
once the spkr set is selected. If the spkr selector is not working then don't blame the relay. Forget the relay(s) for the time being and fix/clean the spkr selector,
check connected wires/joints...
Fixed the switch, and tested relays with power supply...got anything else to help with?
 
...given up, beyond my scope, so parting out a excellent amp with no click on the relays...sigh:thumbsdown:
 
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