NOOB relay based switching questions.

Forum dedicated to helping people debug and troubleshoot non-functional pedals or builds. Please use an clear and informative title, indicating circuit and basic problem. Don't forget to mark the issue as fixed if this is the case.
Post Reply
User avatar
The Rotagilla
Diode Debunker
Information
Posts: 736
Joined: 20 Aug 2007, 18:24
Has thanked: 7 times
Been thanked: 61 times

Post by The Rotagilla »

I've been messing with relay based switching and have the code where I want it but have run into two issues that I could use input on.

1) On a couple of my builds (overdrive/distortion pedals) I'm getting what can best be described as a squeak or metallic ping that comes through my amp whenever the relay switches to the ON state. I'm pretty sure it's not the coding so could I have a microphonic part somewhere? The relay? The switch? Anyone else run across this and is there something I can do to quiet it?

2) I'm using the short shaft SPST momentary switches from Mammoth Electronics and sometimes the pedal doesn't switch smoothly/cleanly. For example...

- The circuit will be on but the LED is off and I have to hit the switch again.
- I'll go to turn the pedal on or off and will have to double tap it to work

This doesn't happen with every switch and it also doesn't happen every time so I'm thinking it's not a coding issue (but wanted to be sure). Does anyone else have experience with these switches and did you run into the same issue?

Thanks in advance.
The television will not be revolutionized.
Top
User avatar
lolbou
Old Solderhand
Information
Posts: 2612
Joined: 18 Nov 2008, 21:38
Has thanked: 305 times
Been thanked: 220 times

Post by lolbou »

What's the code machine? Arduino or something?
The Rotagilla wrote:On a couple of my builds (overdrive/distortion pedals) I'm getting what can best be described as a squeak or metallic ping that comes through my amp whenever the relay switches to the ON state
Is the relay power supply the same as the pedal power supply? Might need some decoupling since the relay coil draws quite a lot of current (could easily be some hundred(s) of mA).
The Rotagilla wrote:- The circuit will be on but the LED is off and I have to hit the switch again.
A SPST is only giving one digital level at a time, so I assume that the LED and the relay are activated by the same logic input. If the code is right, then it should act identically for both, ie all ON when the switch works, and OFF when the switch fails... :scratch:
- Are you a mod or a rocker?
- Uh, no, I'm a mocker.
Top
Post Reply

Return to “Pedal Debugging & Troubleshooting Support”