Convert NO switch to NC switch with AC voltage

BassAmp

Member
2016-03-17 2:41 am
CA
I have a guitar pedal that uses NC momentary SPST footswitches. The switches are pretty sub par.

There is a switch I would really like to replace them with, but this switch is only offered in NO configuration.

I understand there is a way to convert a NO switch to a NC switch using transistors and resistors if there is adequate DC flowing through the switch circuit. However, these switches have roughly 1V AC going through them.

Is there a way to accomplish this that isn't overly complicated?

I understand I could just buy some off the shelf NC switches but I would really like to make this work if possible.
 

BassAmp

Member
2016-03-17 2:41 am
CA
I don't think that will ever happen.

Please forgive my total ignorance here, but knowing that there is 1 VAC to work with wouldn't be enough to come up with a possible solution? Is the schematic necessary to see if there is somewhere else to draw DC power from or to determine possible negative side effects?
 

rayma

Member
2011-04-29 8:37 pm
Since we know nothing about the circuit, hard to say much else about it.
Any circuit changes would require knowing what the circuit is.

I suppose a mechanical arrangement could be made somehow, sort of
a see-saw lever thing. Push down would be mechanically converted to push up.
 
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The most likely scenario is that you are describing a modern, digital piece of equipment, and you measured the 1VAC yourself with your meter. If so, it is just a simple digital, high impedance circuit driven by the switch, and your meter was just rounding up ripple to 1V. Yes, you could invert it, but I personally wouldn't bother.
 
By "overly complicated" I mean something that will take up so much space that it likely wouldn't fit inside the existing enclosure.

Do you think this might be possible with solid state relays, to avoid the clicking sound of mechanical relays?
You could probably use very small signal relays that you won't hear, it's impossible to be certain without knowing the circuit
 

Gnobuddy

Member
2016-03-01 4:10 pm
so what pedal is this?
It's a closely guarded secret, like the schematic. ;)

Reading between the lines just a wee bit, it seems we are invited to help fix this pedal, and maybe create an income stream for BassAmp in the process, but we are not worth enough to be given anything in return, not even minimal information.

Ever see a toddler in kindergarten ask for goodies from another child's lunch-box, without offering to share anything in return? It doesn't work very well even at that age. :D


-Gnobuddy
 

BassAmp

Member
2016-03-17 2:41 am
CA
You could probably use very small signal relays that you won't hear, it's impossible to be certain without knowing the circuit

Thanks, there is no way to know what's going on in this thing under all the goo. I'll just go with some generic switches and call it a day.

It's a closely guarded secret, like the schematic.

Reading between the lines just a wee bit, it seems we are invited to help fix this pedal, and maybe create an income stream for BassAmp in the process, but we are not worth enough to be given anything in return, not even minimal information.

Wow, you are good. Really good. Impressive even. How did you know I was going in to business? Remarkable. However, why did you leave out the fact that I'm also a Kremlin asset and am working closely with the CCP and Tehran and we're controlling your thoughts remotely? Reading between the lines a wee bit, you must be writing a book and you don't want to spill the beans prematurely. You have quite an imagination.

Ever see a toddler in kindergarten ask for goodies from another child's lunch-box, without offering to share anything in return? It doesn't work very well even at that age.

No, I haven't seen this. The implication is that you will only answer a question if you can get something in return. That sounds pretty childish. SMDH.

and here i thought it was because he did not have the schematic and needed to resolve a repair issue.

That's exactly what this is. I just want to make this thing work better. It's a bare aluminum box with no name on it. The circuit board is covered with epoxy. I don't even know if there is another one in existence. I left that out because I wanted to keep the discussion on topic and not have it turn into a thread about the box itself. Really, that's it.

Who would have thought simply asking for help with a repair would be so scandalous?



Incredible.
 

Gnobuddy

Member
2016-03-01 4:10 pm
Who would have thought simply asking for help with a repair would be so scandalous?
Let's look back at some excerpts from your posts:

  • "I don't think that will ever happen" when asked for the schematic.
  • "I would highly doubt that it's audio signal" when asked about the mysterious 1 volt of AC.

  • "Please say that again in English" when someone tried to give you some helpful information.

  • No response at all when asked "What pedal is this?"

  • No photos or other information that might help even the littlest bit.

Try and look at all this through the eyes of a stranger who doesn't know you: Because of the way you chose to word your replies, it looks like you're hiding information and being borderline rude and sarcastic. Repeatedly. Perhaps it wasn't meant that way, but it reads that way.

Your reply to my last post has the same tone: lots of sarcasm, not a whole lot of "Sorry I didn't communicate better, here are the facts."

All this certainly doesn't motivate me to want to help you. But I'll wish you good luck with your pedal repair.

Have a nice day!



-Gnobuddy
 
Convert NO switch to NC switch with AC voltage

When I read this, I was thinking something like the following: When you put a NO switch between two mains phases and then flick it, the applied AC will probably weld the switch contacts together and thus convert your NO switch into a NC switch. Or more probably into a PC switch (as in Permanently Closed)... SCNR :p !

Disclaimer: Don't try this at home or at all!
 

BassAmp

Member
2016-03-17 2:41 am
CA
...the applied AC will probably weld the switch contacts together and thus convert your NO switch into a NC switch. Or more probably into a PC switch (as in Permanently Closed)... SCNR :p !


Oh man, that is absolutely hilarious! That never even crossed my mind. That's exactly what my thread title sounds like!

I should probably fix that. Nah...it's too funny as is!