Normally closed to normally open converter?

[hughesp]

I recently picked up a boss es5, which is a cool device except that it's control outs, which can do cool things like send tap tempo, only work with normally closed inputs (like boss delays).  Seeing as most pedals use NO instead of NC, I was wondering if anyone could help me figure out how to build a device that could go in line to flip the polarity from a NC signal to something that works with a NO tap tempo input?

I'm something of a newbie to this sort of electronics, but I'd be happy to learn!  I imagine some sort of relay would be the way to do this, but mY relay  knowledge is really lacking....

[GibsonGM]

Hi Hugh, welcome to the forum!    I'm sure someone will come along who knows exactly what you need to do - I haven't had the honor of flipping a Boss control out....but it sounds like something could be rigged up using a transistor as an inverter.

In the CE configuration, if you input a voltage to a transistor, the output does the OPPOSITE - it is inverted 180 degrees.   I'd want to know what output voltages are going on, and when, and then a basic circuit could very likely be put together that would take care of this...is it digital, or are there discrete levels?   That kind of info will determine how the thing is built.   

[lars-musik]

Hi Hugh,

some two years ago I was looking for the same thing (or rather a normally closed Carling switch which I couldn't find) for my Boss RC-2 and a fellow member from the German Musikding Forum came up with a MOSFET based switch inverter.



For reference here's the original thread:
http://musikding.rocks/wbb/index.php/Thread/22649-Carling-Taster-Soft-%C3%96ffner-gesucht/?postID=348166

I haven't tested that but I wish you good luck with it!

[hughesp]

Cool! 

I'll have to do some voltage readings.  From what I've read (but I'll need to test to confirm), the voltage would likely be below 5v.

I'll have to see if I can get that switch inverter circuit a try..

[GibsonGM]

There ya go, Hugh!  Easy to find Mosfet, too. If you plan to do other audio "stuff", get a bunch of them!