Relay Not Working with Footswitch

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jhaas
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Relay Not Working with Footswitch

Post by jhaas »

I am attempting to implement a single-relay switch using the D'Lite scheme as a guide.

I am using the otherwise unused 5V tap on my PT to power it.

I have it wired as shown in the attached schematic, with the exception of a 47R resistor where the schematic show a 56R.

When I use the front panel switch, the voltage across the relay coil toggles between 7V and 0V and the switching works wonderfully.

When I plug in a standard marshall type footswitch (with LED) the voltage across the coil toggles between 7V and about 1.8V, and the 1.8V is not low enough to switch the relay.

What am I doing wrong?
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ToneMerc
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Re: Relay Not Working with Footswitch

Post by ToneMerc »

IIRC, the Marshall style FS with the LEDs needed to be rewired. I would research it more but I'm headed out the door.

TM
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Dr-Joned
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Re: Relay Not Working with Footswitch

Post by Dr-Joned »

If this is the footswitch that I have attached, then yes it would need to be rewired. The 5v zener would not allow the voltage to pass unless the effects switch was in the off position. The circuit would then has to be polarized correctly or there would be a 1.4 or 1.6 v drop across the other diode and led.
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jhaas
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Re: Relay Not Working with Footswitch

Post by jhaas »

Guys, Thanks for the replies.

Just to close the loop - I didn't want to rewire the footswitch for this, so I changed the way I am implementing to relay to match what is shown in the attached schematic.

This seems to be working well.
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