JCA channel switch and jack mod

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Jay
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JCA channel switch and jack mod

Post by Jay »

Okay, guys. If you guys want a switch on the front of your amp to switch channels without using the footpedal, here"s a good one. This also lets you still use the footswitch when you plug in the controller without worrying about what position the switch is in.

The two grey wires on the jack are connected to the small toggle on the front panel. When switched, the amp goes from the OD to the Normal channel. Only problem is, the switch has to be switched back off or the amp will not switch channels back and forth when the footswitch is plugged in.

Image

Switch is on the left. Something like this should work for the mod: SWITCH

Image

Replace the jack above with this: JACK It has a shorting bar that will disconnect when the jack is plugged in. So, the blue wire will be soldered to the TIP terminal. One of the switch wires will be soldered to the SHUNT terminal (the small spring bar that contacts the inside of the TIP terminal). Then, solder the black (ground) wire and other switch wire to the RING terminal on the jack. So, when the footswitch is NOT connected, the panel-mount switch controls the channels. When the footswitch is plugged in, it will disable the panel switch and leave the footswitch as the dominant controller. Simple, easy, convenient. Get to work!

Thanks to Grimespace for pics of his amp.
Loud Noises
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Tortuga
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Re: JCA channel switch and jack mod

Post by Tortuga »

Haven't had time to do this change yet. Will report back as soon as I've had the chance to do so.

Is there a way to add an LED that will indicate when the OD channel is kicked in? I could replicate the wiring on the footswitch, but I believe that the LED would only work when using the front panel switch. I'd like to have the LED function independent of which switch is being used, like what I've heard the HDM does.
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Jay
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Re: JCA channel switch and jack mod

Post by Jay »

Should be no problem. Should be as easy as dropping an LED across the terminals of the footswitch jack. While the switch is engaged, the switch shorts it, and switches the channels. When the switch is open, just enough juice flows through the LED, but not enough to engage the relays.
Loud Noises
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