Anyone experienced with Ampeg V series repairs?

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jaysg
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Anyone experienced with Ampeg V series repairs?

Post by jaysg »

I have a V-4B with a bad Ultra-Lo switch. I can't see how it's made installed and taking it out looks like a pain. Can this thing be cleaned with deoxit?

(the switch is capable of killing the signal on either or both channels...and does)
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selloutrr
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Re: Anyone experienced with Ampeg V series repairs?

Post by selloutrr »

yes it can be lubricated but use caig fade lude not deoxit.
fliptops sells replacements if you need a new one.

V-4 family is a bitch to work on, They are very popular here for desert stoner rock.

Very high voltages.
Brittle PCB's - over heat them and they peal off.
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jaysg
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Re: Anyone experienced with Ampeg V series repairs?

Post by jaysg »

selloutrr wrote:yes it can be lubricated but use caig fade lude not deoxit.
I have deoxit and some other brand of contact cleaner. FaderLube I assume?

http://store.caig.com/s.nl/sc.2/category.183/.f
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selloutrr
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Re: Anyone experienced with Ampeg V series repairs?

Post by selloutrr »

that's the stuff.
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David Root
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Re: Anyone experienced with Ampeg V series repairs?

Post by David Root »

I have a '74 V4B and a '75 SVT, have not noticed any peeling PCB traces in mine. The hum pots were fried when I got them (very common) and no they are not the easiest to work on, but the tone is worth it!
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selloutrr
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Re: Anyone experienced with Ampeg V series repairs?

Post by selloutrr »

The inverted design makes the heat from the tubes bake the circuit board causing it to become brittle and shrink leaving the traces fragile.
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fuzzheimer
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Re: Anyone experienced with Ampeg V series repairs?

Post by fuzzheimer »

Reminds me I've got an iron set pulled from an old basket case vt-40...I need to work that stuff into a project!
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Travst
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Re: Anyone experienced with Ampeg V series repairs?

Post by Travst »

I love the V4. I re-capped the last one and dropped in new lamps and a faceplate, plus a 3-prong cord. Then came a full tolex job as the cab came in bare wood, plus some new hardware. Everything said here is spot on, the pads come off the boards very easily.

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jaysg
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Re: Anyone experienced with Ampeg V series repairs?

Post by jaysg »

Progress report...it seems like some of the spray gets into the switches, but not much. It was cold biased, so now it's at about 90W with a set of GT chinese 6550Cs with a rating of 4...which I think means earlier breakup than I'd want for a bass amp. I couldn't find the ultra-lo switch at fliptops, but they want $35 for the ultra-hi. Pulls only, from the looks of it.

Looking at the V4 above with a new power switch...the standby switch on the subject was bad. Should I replace the power switch while I'm at it?
paulster
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Re: Anyone experienced with Ampeg V series repairs?

Post by paulster »

You might be able to get the switch as a new part from Ampeg. When they did the SVT-VR they had to re-manufacture the rocker switches, so they may have the appropriate part.
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Richie
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Re: Anyone experienced with Ampeg V series repairs?

Post by Richie »

i sent you a PM. i may have some NOS switches,i'll have to look.
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selloutrr
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Re: Anyone experienced with Ampeg V series repairs?

Post by selloutrr »

as long as you are in the amp you might as well replace anything you have doubts about.
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