Need some tech help figuring out A Fender Amp footswitch issue.

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Reg18
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Need some tech help figuring out A Fender Amp footswitch issue.

Post by Reg18 »

My Fender Proreverb has the original 2 button Vib/Trem footswitch but it’s not working anymore.
It was initially when I got the amp then it’s "past participle of get" more and more intermittent until it doesn’t work at all for vib or Trem now!
I have used contact cleaner on both the switch’s and the RCA looking connections into the amp, and I also replaced both footswitchs with some I had around to check it wasn’t them.
Still no luck!
The amp hums a lot more with the reverb knob on compared to Having it completely off.
Can someone think of a next step to try?

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jeremyb
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Re: Need some tech help figuring out A Fender Amp footswitch issue.

Post by jeremyb »

Could be the tube that drives the trem or as simple as a burnt out resistor like in my AC15 that killed the trem, seems unlikely to be the footswitch :(
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Re: Need some tech help figuring out A Fender Amp footswitch issue.

Post by Starfire »

These are prone to problems. The wire is pretty fragile, so it could well be broken. I have the same issue with the one on my Princeton. I was planning to cut the cable down, which should hopefully remove the damaged section and fix the intermittent problem. I don't really understand why they come with about 3.5m of cable anyway.

I'm sure I saw a thread on TDPRI or somewhere where someone had replaced the wire with heavier stuff less prone to breaking. Haven't been able to find it again though.

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Re: Need some tech help figuring out A Fender Amp footswitch issue.

Post by Reg18 »

jeremyb wrote:Could be the tube that drives the trem or as simple as a burnt out resistor like in my AC15 that killed the trem, seems unlikely to be the footswitch :(
I changed the reverb tube today to check that, reverb still works just not via the footswitch. Would a dodgy resister be intermittent or just “goes or it doesn’t”?

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Re: Need some tech help figuring out A Fender Amp footswitch issue.

Post by Reg18 »

Starfire wrote:These are prone to problems. The wire is pretty fragile, so it could well be broken. I have the same issue with the one on my Princeton. I was planning to cut the cable down, which should hopefully remove the damaged section and fix the intermittent problem. I don't really understand why they come with about 3.5m of cable anyway.

I'm sure I saw a thread on TDPRI or somewhere where someone had replaced the wire with heavier stuff less prone to breaking. Haven't been able to find it again though.
Would you say it’s likely at this end? So cut it back a few cm and resolder?
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Re: Need some tech help figuring out A Fender Amp footswitch issue.

Post by Starfire »

You could try it. You might be able to figure out where the likely break is if you move the footswitch and the cable around to see if you can get the reverb working again.

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Re: Need some tech help figuring out A Fender Amp footswitch issue.

Post by sizzlingbadger »

If you short the socket on the back of the amp with a short piece of wire and it works ok then you will know it is the footswitch that has the issue. Do you have a multimeter to check the footswitch cable ?
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Re: Need some tech help figuring out A Fender Amp footswitch issue.

Post by goldtop0 »

I've had two of those Rev/Vib pedals go wonky in the past year or so, the wiring in them is atrocious.
I've given them to my amp man for an easy fix on both occasions.
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Re: Need some tech help figuring out A Fender Amp footswitch issue.

Post by Molly »

Plug a TRS cable in to the footswitch socket and separately short the ring and tip with the sleeve to see if that operates the reverb / trem.

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