Fender Gibbs Reverb pan questions

[mresistor]

Hi guys   I recently repaired a 1967 Deluxe Reverb amp and one of the problems was that the reverb didn't work.  So to make a long story short I found a like new looking Gibbs pan in it marked as a 1967 and the in and out impedances are wrong for the Deluxe, or so I think. The input measures 1.2 ohms and the output measures 166 ohms.


As you know the modern reverb tank replacements are 8 ohm input and 2250 ohm output.


Can anyone shine a light on what this Gibbs reverb pan would be for?   

[mresistor]

Oh ok  further reading tells me that the impedance is higher than the dc resistance at the rca jacks. So this tank would be usable for a blackface reverb amp if it worked.


It doesn't but it looks just fine. The output works but the input doesn't.  On the end that doesn't work one of the little ferrite beads that attatch to one spring and to the tubes via a very thin copper wire is touching the metal where it enters..  The other three are suspended without touching the metal.  It's hard to describe. A couple of the little ferrite beads were also found in the reverb bag, I think they are from a different tank. Maybe I can use one to fix the one spring hanger..

[tubeswell]

Or, if you like mad science, gently ‘take apart’ the non-working transducer unwinding the winding until you find where it’s broke, and fix it. (Rather you than me.)

[dogburn]

As far as compatibility, the F stamped in there indicates it is a suitable pan for Fender tube amps like the Deluxe Reverb, as far as input & output impedance. On the other hand, that pan has obviously been repaired before because those wires going to the transducer coil are not original and the coil also has some gunk on it indicating it's been repaired, maybe poorly.

It could probably be fixed with some delicate surgery, but it can be frustrating because those parts are so small and finicky. You might be able to scavenge parts from one pan to fix the other. If you go to Surfguitar101.com, there are many threads discussing reverb pans - some discuss repairing them, and there is one dedicated to deciphering Gibbs pan codes.

[mresistor]

HI dogurn   thanks for that info.  I did register at the 101 site you provided and proceded to find the thread on Gibbs pan documentation.  Interestingly I found there that the "F" on the inside by the input jack means "Medium Decay". 


Also I find that the wires from jacks to inductors look very original to me. The solder joints look to be untouched and factory made.  What leads you to believe the wires are not original?

[dogburn]

The old pans I'm familiar with had thin, plastic (PVC?) covered wires - it's possible older Gibbs pans had cloth covered wires - so I could be wrong on that count.

[Carlsoti]

The little ferrite beads are actually magnets polarized in a very specific way. Make sure you try each position to make sure you're getting all the action out of it that you're supposed to. I broke myself of repairing spring tanks working on an old Supro with the 2 spring cardboard box reverb. Most replacement tanks are $30. Most of the time, you don't get that surfy sproing as you would from a good old tank, but also, I don't get those fruitless hours back.

[mresistor]

Yes it sure is a painstakng process and repair and not for everyone.  So far I haven't spent much time on it.  Maybe I should offer it up for someone who wants to invest the time and patience and skill necessary to restore it. It was working in the DR when it arrived but had to turn the knob way up to get some sound out of it.  Hooked it up to one of my PRs and it doesn't make any sound at all.   So something is definitely amiss.

Thanks everyone for your inputs,,

[Bieworm]

Or, if you like mad science, gently ‘take apart’ the non-working transducer unwinding the winding until you find where it’s broke, and fix it. (Rather you than me.)

I once took on that adventure. Eventually I gave up and bought a new tank. This was a modern tank that had a broken transducer tho...