Is your unobtainium power switch worth $5 and an hour or so of your time?

@c.coyle is there a reason your schematic differs from @K7sparky's? He has AC connected to M1 and the transformer to M2. Switch goes from gate to M2 in both.

No, as pointed out by others above. This is just the way my blues-based brain grasps it best. Everything flows from left to right. It helps me if I think of the triac as a pair of open contacts (I know) until the power switch is closed and the gate is fired, at which point the circuit is completed.

EDIT: I have no formal training, and often I have problems translating even simple schematics into physical arrangements on a board or chassis. Rearranging the schematic on paper sometimes helps.
 
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You don't need a snubber with an alternistor triac. It's designed for inductive loads. As far as connecting the AC, does this help?

View attachment 1350973
Hi C. Coyle
You don't need a snubber with an alternistor triac. It's designed for inductive loads. As far as connecting the AC, does this help?

View attachment 1350973
This schematic is a much more intuitive. I really appreciate the help and will try this tonight. I think the schematic I loaded is the one that someone mentioned was incorrect. Quite possibly my problem. ( Also I should have downloaded the data sheet on the Alternistor. I will let you know and hope all works. Thanks
 
I am hoping someone can help me. I was given a KR-9600 with a non-functioning power switch. Someone had just hardwired a bypass on the switch. I took the switch apart and thought I could repair it. However, the side that switched the AC was pitted badly, not only at the round contact, but also the center terminal. It is so bad that the spoon will not pivot, but falls out of place and binds up the switch. Now, I want to use a triac for the AC which will be controlled by the working side of the switch. I also want to use the same side of the switch to activate some kind of relay to open/close what was originally on that side of the switch. I am not sure what that does, other than it is grounding some circuit, seems low voltage signal perhaps? Is there a solid state device I could use, something as simple as the triac for AC? Or should I just get a small relay?
Any help would make my life just that much better and would be appreciated.
 
I am hoping someone can help me. I was given a KR-9600 with a non-functioning power switch. Someone had just hardwired a bypass on the switch. I took the switch apart and thought I could repair it. However, the side that switched the AC was pitted badly, not only at the round contact, but also the center terminal. It is so bad that the spoon will not pivot, but falls out of place and binds up the switch. Now, I want to use a triac for the AC which will be controlled by the working side of the switch. I also want to use the same side of the switch to activate some kind of relay to open/close what was originally on that side of the switch. I am not sure what that does, other than it is grounding some circuit, seems low voltage signal perhaps? Is there a solid state device I could use, something as simple as the triac for AC? Or should I just get a small relay?
Any help would make my life just that much better and would be appreciated.
I suggest you start a new thread to deal with this problem , as the troubleshooting of it and adding a relay is not directly related to the triac installation. That extra set of contacts appears to be part of a muting circuit. Post in DIY or Solid State forum . Good luck! BTW, you could sign up as a Subscriber and post a Want-to-Buy in Bartertown. :)
 
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Unobtainium?

I think he's referring to the fact that you need to know how to correctly misspell unobtainium to find this thread. But since unobtainium and unoptainium aren't real words, I suppose it's OK to substitute a p for the b.

I also want to use the same side of the switch to activate some kind of relay to open/close what was originally on that side of the switch. I am not sure what that does, other than it is grounding some circuit, seems low voltage signal perhaps? Any help would make my life just that much better and would be appreciated.

The other side of the switch is for the muting cicuit. You definitely don't want to mix it with 120VAC. Train wreck.

The easiest solution is to search ebay for "ALPS TV-5 ON/ON 6 Pin Toggle Power Switch", (no affiliation) and swap the the all new identical guts onto your original KR-9600 toggle assembly. Then add a triac or a relay, or just run it as-is.
 
I think he's referring to the fact that you need to know how to correctly misspell unobtainium to find this thread. But since unobtainium and unoptainium aren't real words, I suppose it's OK to substitute a p for the b.
Yup, Been there, done that, saved the link :thumbsup:
 
My solution is to use a double pole relay, one side for AC to the transformer, the other side for the muting circuit. I will use the good side of my toggle switch to run AC to the coil of the relay. I am afraid to open my toggle switch anymore; I have done it a few times and am afraid of the tabs snapping off. Otherwise, I might have gone with the replacement guts.
 
I am ready to proceed with this mod on my LR-9090. Got the triac, some wire, resistor,etc. Being somewhat of a newbie to this stuff, I think I have it and then it eludes me. My issue is Sparky's drawing versus the others where M1 and M2 are switched. I understand the triac is bidirectional, but you must run the gate to the proper spot as a result. Then the reference to SW1 and SW2 positions. Which is which on the switch. Is one the open side that is not powered? I have not seen a reference to the switch position/terminals. Sparky notes" Power switch: Lead 1 100 ohm resistor and goes to gate G. lead 2 goes to M2. How do I know lead 1 and 2 and where they are on the switch?

Thanks for any help.
 
I am ready to proceed with this mod on my LR-9090. Got the triac, some wire, resistor,etc. Being somewhat of a newbie to this stuff, I think I have it and then it eludes me. My issue is Sparky's drawing versus the others where M1 and M2 are switched. I understand the triac is bidirectional, but you must run the gate to the proper spot as a result. Then the reference to SW1 and SW2 positions. Which is which on the switch. Is one the open side that is not powered? I have not seen a reference to the switch position/terminals. Sparky notes" Power switch: Lead 1 100 ohm resistor and goes to gate G. lead 2 goes to M2. How do I know lead 1 and 2 and where they are on the switch?

Thanks for any help.
It does not matter which AC connection on the switch goes to which lead as long as one side goes to the triac Gate and one goes through the resistor to M2. It also does not matter which lead the resistor is on as long as it is on one of the leads between the switch and the triac. There should not be any other connections to the switch, remove the snubber capacitor.

EDIT: spelling, word choice
 
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Thanks merlynski. I am looking at taking the alps switch out to inspect and clean up a bit. My switch was replaced years ago and only recently started to arc again on occasion. It looks like pulling the switch is a bit of a pain. Perhaps I can leave it in place and see if all works. Worth a chance? Do most take the switch out and clean? The bottom bolt and nut I can get easily, but the top one is hard to get at. I can get a little wench on the nut, but with the red loctite goobered all over it, the threaded shaft wants to move. Maybe have to try and remove the loctite and hold the rod with a little pliers. Sheesh, more of a pain than I first realized. I certainly want to save this bad boy. I have owned it since my days of working at Lafayette and I sold a ton of these. Quite sentimental for me.
 
Thanks merlynski. I am looking at taking the alps switch out to inspect and clean up a bit. My switch was replaced years ago and only recently started to arc again on occasion. It looks like pulling the switch is a bit of a pain. Perhaps I can leave it in place and see if all works. Worth a chance? Do most take the switch out and clean? The bottom bolt and nut I can get easily, but the top one is hard to get at. I can get a little wench on the nut, but with the red loctite goobered all over it, the threaded shaft wants to move. Maybe have to try and remove the loctite and hold the rod with a little pliers. Sheesh, more of a pain than I first realized. I certainly want to save this bad boy. I have owned it since my days of working at Lafayette and I sold a ton of these. Quite sentimental for me.
Putting in the triac will stop further damage to the switch, but not clean it up. If it was me, while I am in there I would clean up the switch, then it will never be a problem again. The gate current is very small and the switch contacts will, maybe, not conduct as well until cleaned up. Loctite can be softened with some heat, like the tip of a soldering iron on the nut or bolt.
 
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Took your advice and pulled the switch. Yes, the power contacts looked like crap, but better now having dragged some crocus cloth across them. Still some irregularities on the surface which should be good for make numerous contacts as noted by others. Tomorrow on to the triac to preserve the gains.
 
Success. This was one of the best threads I have read over the years. My 9090 is running with no arcing on the power switch now thanks for all the input from Sparky and others. Very grateful and it only cost me a few dollars and a bit of a learning curve.
 
Looks like I spoke too soon. My unit was functioning fine this afternoon as I tried it for short periods. Now tonight it doesn't totally turn off. The off position drops the amplitude to a much lower level, like before the relays kick in when turning it on. Not sure what happened. Pull the plug and of course it goes off, but comes right back on when plugged in. I was so elated this aft, and the unit sounds so good. I am kind of decimated. ~:( Any thoughts? wired incorrectly, triac go out, relay or switch stuck? When I turn the power knob from off to on, the relay clicks on inside the unit for full volume control.

Got my triac out of China on ebay. They sent me a 600 volt rated unit, but I judged that would be OK. Maybe that was not a good decision.
 
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