Momentary not working every time in Boss pedal

[gmr1]

moved a boss pedal into a new housing, and used a full size 2 lug momentary switch for the footswitch. Seems that if you switch the pedal off or on quickly, it doesn't always work. Any tricks to making this sort of switch more consistent? If you go somewhat slow it works perfect, it's just once out of 10 that a quick push doesn't trigger. Thoughts?

[Paul Marossy]

It's probably your switch. It most likely has too much "bounce".

[MoltenVoltage]

Different switches have very different bounce characteristics.

You might have to try a number of different switches until you get one that works consistently.

Also make sure the switch is the same as the one you are replacing - whether its normally open or normally closed.

[gmr1]

It's probably your switch. It most likely has too much "bounce".

It's odd as the same type of switch seemed to work fine in the past. Maybe I'm being too critical. IIRC, these are the "soft touch" momentary switches that small bear carries.

Is the "bounce" a physical char. of the switch? No way to lessen its response... resistance in series with the switch, a small cap... I'm grasping here! 

I have a bunch of these switches... had them earmarked for re-houses. Oh well. Any recommend a full-size momentary for Boss switch replacement?

[Paul Marossy]

Is the "bounce" a physical char. of the switch? No way to lessen its response... resistance in series with the switch, a small cap... I'm grasping here!  

Yes, it is a physical characteristic of the switch. I'm not sure what could be done to improve it. I've heard of "debouncing" circuits before, but I have no experience with them.

I guess you either need to live with it, get a better switch or build a debouncing circuit so it works every time. Here is a page I found on debouncing: http://www.elexp.com/t_bounc.htm - maybe it will help.

EDIT: Here's another page that looks informative: http://www.ganssle.com/debouncing.pdf

[gmr1]

Interesting stuff Paul, Thanks. Seems like a small debouncing circuit could do a lot of good in making most switches work in this application. I'm not sure if I have the chops to figure one out, but that second article suggests it's not out of grasp.

Yes, it is a physical characteristic of the switch. I'm not sure what could be done to improve it. I've heard of "debouncing" circuits before, but I have no experience with them.

I guess you either need to live with it, get a better switch or build a debouncing circuit so it works every time. Here is a page I found on debouncing: http://www.elexp.com/t_bounc.htm - maybe it will help.

EDIT: Here's another page that looks informative: http://www.ganssle.com/debouncing.pdf

[Paul Marossy]

I've never had the need arise for a debouncing circuit, but a basic one looks simple enough to incorporate into a circuit.

It seems to be dependent on the application, too. When I built my tempo controller box for my Boss DD-5, it didn't seem to care that I used a cheap RadioShack momentary switch. It works. But I guess it's a different matter when it's activating an FET flip-flop circuit. I guess speed counts in that application whereas the DD-5 is just averaging the time between the contacts, so a little switch bounce doesn't bother it.

[MoltenVoltage]

Building a debounce circuit is a whole lot of trial and error and error and error, but you can do it if you are persistent.

[gmr1]

Building a debounce circuit is a whole lot of trial and error and error and error, but you can do it if you are persistent.

Ha! looks it. with no base numbers to work with, it seems like a lot of guessing.

I'll likely just try to find another switch and save these for something not so picky.