Question about Relay Switching for pedals....

All frequent questions on switching: true or not true bypass, transistor-based or mechanical.
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lukatosh
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Post by lukatosh »

Dear friends... well i would like to apologise myself is this post must be in other section of this forum, due to the inactivity of other sections I post this question here...maybe it'll be usefull for more than one Diyer.

several times i had problems with the 3pdt and poping... searching in internet i've read several times about the relay switching way... replacing the 3pdt by a simple momentary stomp switch... some popular brands implement this system on their pedals, to avoid pop, more space to the battery, cheaper... etc etc

i look for some info but i can't find indications to build the system, some times some diagrams use transistors, other ones uses integrated cricuits...Differents desing drain more current... Flip flops...microcontroles... i've found a very simple desing ( see atachment) but... it looks so simple!!, so... i'm very confused about wich way to go :(

Does anyone have a diagram of a tested and working desing?. also, maybe the relay specifications... or even better a pcb designed for implement this bypass switching??

plase, take a look at this from an argentinian forum... but no design or mayor info :(

Image

i'll be so gratefull for your help! thank you so much!!... i've read some info... but i'm writing from chile.. some times it's hard to me to understand english :(

Excuse my bad english...
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mictester
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Post by mictester »

The circuit you show will work but will kill your battery - it will draw current whenever the coil is active.

I put a much better circuit up here a while ago - it uses very little current https://www.freestompboxes.org/viewtopic ... 13&t=13295. The only little problem is that you MUST use a LATCHING relay. I use the Takamisawa AL5WN-K. The circuit only draws current when the relay changes state to "on" if you leave out an LED. The current drawn will be about 100 µA so it won't affect your battery life at all!

Remember - it MUST be a LATCHING relay!
"Why is it humming?" "Because it doesn't know the words!"

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