True Bypass wiring

[Zouto]

Hello, I‘m looking for true bypass wiring diagram of a 3PDT switch with bi-color LED, (changing from red to blue).
Thanks for help, hints & info
Zouto

[TomCarlos]

And what exactly are you using this for? A wah pedal? Something else? If you search the net for "True Bypass", you will find diagrams.

[J M Fahey]

Hello, I‘m looking for true bypass wiring diagram of a 3PDT switch with bi-color LED, (changing from red to blue).
Thanks for help, hints & info
Zouto

The true bypass section is easy, just post some data on the actual bi-color Led you want to use (hint: datasheet)

If you search the net for "True Bypass", you will find diagrams.

Thatīs how he got here in the first place

You might at least suggest one

[TomCarlos]

I can do that...

True Bypass Wiring Scheme... https://stinkfoot.se/archives/2233

[Zouto]

I need it for a vintage big Box1990s EHX Frequency Analyzer. There are no power and status LEDs, so it would be nice to have power indicator plus FX status LED on one switch without drilling any additional holes. It is important to have FX in- & output grounded in bypass to avoid carrier signal leaking through. Switch
https://www.taydaelectronics.com/ill...-red-blue.html

[Mark Hammer]

I'm not saying it WILL be the case in this instance, but bear in mind that many "vintage" effects that used SPDT stompswitches - basically all we had back in the day - had their circuits tweaked so that effect and bypass had roughly similar output levels. The traditional style of bypass-switching with SPDT switches left the input jack hard-wired to the input of the effect circuit board, and simply directed the output jack to either the output of the circuit OR to the input jack. Often, that would mean that the input stage of the effect could "load" down the signal. With one pedal in your chain, it wouldn't matter all that much, especially when pitted against use of a long cable and unbuffered signal. But if you had 2, 3, or 4 pedals like this in your chain, even with every one of them ostensibly "bypassed", your signal got seriously loaded down, with much tone-suckage.

True-bypass switching, with 3PDT switches (thank you Mike Fuller) allowed for complete elimination of such loading, and the addition of status LEDs that could let one keep track of which of their 18 pedals on the board were off or on.

But some folks who converted a vintage pedal from SPDT to 3PDT noticed that bypass would sometimes result in a noticeable volume increase. Why? Because the effect circuit was tweaked to compensate for the effects of the loading by having a deliberately lower output level. Obviously, for something with a potentially MUCH higher output (e.g., an older Big Muff), such a drop is moot. But for anything intended to have the same output level in effect AND bypass modes, this would sometimes occur.

So, get to know the circuit of your Frequency Analyzer, and how it might (and I stress, might) yield a slightly lower output in effect than in true-bypass mode.