Testing / Fixing a Reverb Tank

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Molly
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Testing / Fixing a Reverb Tank

Post by Molly »

Think the reverb tank in my Two Rock has packed in. I'm not sure how to test it but there's no continuity between the plugs. Could one of the chaps here clarify how you test them?

Thanks.

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Re: Testing / Fixing a Reverb Tank

Post by sizzlingbadger »

Measure the input and output resistance is the first step. You won't get continuity between the input and output, thats normal.
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Re: Testing / Fixing a Reverb Tank

Post by olegmcnoleg »

Have you been hitting it with your guitar again?

It is obvious that the amp is totally f****d. I'll give you $50 for it.

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Re: Testing / Fixing a Reverb Tank

Post by Bg »

sizzlingbadger wrote:Measure the input and output resistance is the first step. You won't get continuity between the input and output, thats normal.
I'd also give it a visual, its usually the connection to the springs that breaks.... magnifying glass at the ready :)
So, is that low alcohol or no alcohol at all? mmmm, no alcohol, do you want to try it? Noooooooooo.

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Re: Testing / Fixing a Reverb Tank

Post by Molly »

Thanks chaps. Had one fail in the past and was able to fix it but that was an obvious wire broken off. No such thing here. Found this link. Trusting the advice is accurate.

https://mesaboogie.zendesk.com/hc/en-us ... nk-is-bad-

Will take another look after tea.

Cheers.

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Re: Testing / Fixing a Reverb Tank

Post by Conway »

Are you sure it’s not the tube driving it that’s the problem?
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Re: Testing / Fixing a Reverb Tank

Post by Bg »

he'll be eating his birdseye fishfingers with chips and frozen peas.
So, is that low alcohol or no alcohol at all? mmmm, no alcohol, do you want to try it? Noooooooooo.

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Re: Testing / Fixing a Reverb Tank

Post by Conway »

Bg wrote:he'll be eating his birdseye fishfingers with chips and frozen peas.
He already said it’s pizza night, tonight.
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Re: Testing / Fixing a Reverb Tank

Post by Molly »

Conway wrote:
Bg wrote:he'll be eating his birdseye fishfingers with chips and frozen peas.
He already said it’s pizza night, tonight.
It was delicious! I'm a master chef, me. :thumbup:

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Re: Testing / Fixing a Reverb Tank

Post by Molly »

Conway wrote:Are you sure it’s not the tube driving it that’s the problem?
Crossed my mind. Will check that if the tank tests OK. :thumbup:

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Re: Testing / Fixing a Reverb Tank

Post by Conway »

Molly wrote:
Conway wrote:
Bg wrote:he'll be eating his birdseye fishfingers with chips and frozen peas.
He already said it’s pizza night, tonight.
It was delicious! I'm a master chef, me. :thumbup:
Hell yes. :wink:
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Re: Testing / Fixing a Reverb Tank

Post by Molly »

sizzlingbadger wrote:Measure the input and output resistance is the first step. You won't get continuity between the input and output, thats normal.
Thanks for that. I followed that using info from the link below: "...put your ohmmeter leads across the tip and shield of the reverb tank’s return cable (the shielded cable). For most MESA amps with tube reverb circuits, the reading at the shielded cable's jack will be approximately 200Ω. Leaving a lead on the shield of the return cable, move the other lead to the tip of the input cable. When you read impedance of the input (the thinner, unshielded RCA cable), the reading will be approximately 1Ω. If either point reads open (.000) the tank is at fault."

I got 232 and 1. Didn't get .000. So, that's good news I guess. Next to find out which is the reverb driver tube.

Cheers.

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Re: Testing / Fixing a Reverb Tank

Post by Molly »

sizzlingbadger wrote:Measure the input and output resistance is the first step. You won't get continuity between the input and output, thats normal.
Looked at the tubes. Don't know which one is the reverb driver (can't find that info online for the Studio Pro Plus 35 - still looking) but did note that one tube had been swapped out. The TR website says the reverb tube should be a 12AT7 but at the moment they're all 12AX7. Could it be that this tube is the wrong one for for the reverb and that that's the reason it's not working?

Thanks again all.

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Re: Testing / Fixing a Reverb Tank

Post by Conway »

I have a PDF of the manual. It should be a 12AX7 in V3.
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Re: Testing / Fixing a Reverb Tank

Post by Conway »

The one you have circled in V4 is the tremolo driver and it should be 12AX7WA (high current tube).
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