Pioneer SX-3600 speaker switch question

My best friend picked up an SX-3600 in mint shape except for one thing. The speaker selector switches won't "hold" your choice in place. Are they supposed to be an electronic switch or are they a 2-way switch like the "loudness" button, etc? I didn't think they were electronic style like on the SX-3900. It's a "dual switch" set-up and so we are looking for a replacement switch for it. Spent a couple of hours cleaning it and still no go.

Any input is appreciated as always!

Switch Problem

This is a reasonably common problem on the SX-3500/3600 (also SX-620/720, black dial versions). I’ve both seen this described in eBay ads and personally have had two of these through my door that suffered from this symptom, both proved to be same problem. IMO, it's simply a poorly designed part on this switch. The internal mechanical "ratchet" mechanism fails when a tiny plastic pin (molded as part of the plunger - that’s what I call it, it might also be called a core?) breaks. If I recall correctly, it's a bit of a challenge to access the switches on the PCB, but is doable. Options:

1. Remove the spring so you can push (and pull) the switch to the desired position. See caveats following; once you pull the c-clip (holds in the plunger), GREAT care is required. I have not tried this remedy, but can’t see why it wouldn’t work; better than a non-workable switch, but certainly not an ideal solution.

2. Repair the broken part on the plastic "plunger". This I have done. It's minute, detailed work - a magnifier is recommended. This involves re-attaching the broken center pin (super glue). It should still be inside the switch, as least the ones I found were. There is no guarantee of performance on this repair; both worked, one perfectly, the other not a smoothly as I would have liked. I no longer have them so don’t know how they held out. If the molding broke, well, how good can glue be? Detail junkies like me have to try anyway!

Caution: Pulling the plunger calls for great care! Small parts inside!

3. Replace the entire switch. Of course, you have to find one first.

The speaker switches are on or off, the current flows or it doesn't. The loudness/tape monitor switches are likely two position, but all of these are subject to the same design weakness.

Hope this helps.

Any photos of the repair you did? I've got the switches out and access to the pins, they seem fine but there's a chunk of plastic about the size of two or three grains of sand in there that looks like it used to guide the pin in place. I have two switches with issues, hard to believe this isn't a more common problem. I'll probably just end up pulling the plunger spring for manual control.

I think I fixed it.

I was out at the local electronics salvage shop nosing around and I found some switches similar to the broken ones in my Pioneer. There was a 12 pin model with two position switch and a six pin model (what I needed) but it needed to be held in position or the spring would keep it in the extended position. I noticed the 12 pin switch had a guide pin held on by the spring and the six pin didn't. I bought a bunch of each and went to work.

The first photo is the original Pioneer Switch opened up, it pulls apart fairly easily. The inside of the top half is on the right, the little piece that broke off is in it, it's part of the heart shape guide path from the left side half that the gold pin rides in.

Picture two are my donor switches, notice the guide pin on the 12 pin switch held in by the spring.

Picture three is the six pin with the guide pin installed, giving me the option of having the switch pushed in or extended without having to hold it.

A little soldering and voila....fixed stereo/mono and loudness switches.

Of course in the process of testing everything I found out the tape monitor switch is now useless as well, good thing I got extra parts....

None of the spring loaded push-button switches on my SX-3600 will engage. It is now being salvaged for parts.

Unfortunately, some contact cleaners (Caig DeoxIT D5 is NOT among these) will cause the latching mechanisms on pushbutton switches to fail.

The reason for this is that the cleaner attacks some plastics.

Fred Longworth

Bone Yard said:

I was out at the local electronics salvage shop nosing around and I found some switches similar to the broken ones in my Pioneer. There was a 12 pin model with two position switch and a six pin model (what I needed) but it needed to be held in position or the spring would keep it in the extended position. I noticed the 12 pin switch had a guide pin held on by the spring and the six pin didn't. I bought a bunch of each and went to work.

The first photo is the original Pioneer Switch opened up, it pulls apart fairly easily. The inside of the top half is on the right, the little piece that broke off is in it, it's part of the heart shape guide path from the left side half that the gold pin rides in.

Picture two are my donor switches, notice the guide pin on the 12 pin switch held in by the spring.

Picture three is the six pin with the guide pin installed, giving me the option of having the switch pushed in or extended without having to hold it.

A little soldering and voila....fixed stereo/mono and loudness switches.

Of course in the process of testing everything I found out the tape monitor switch is now useless as well, good thing I got extra parts....

Click to expand...

Very nice work.

Doc