Need help figuring out this reverb driver transformer (Gibson e6400)

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JW

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Here's a scheamatic: http://i142.photobucket.com/albums/r106/capnjuan/gibson%20falcon/GibsonGA19MaestroM216.jpg

It's a Gibson Falcon GA19 RVT The original transformer was open, so I replaced it with an off the shelf fender reverb driver transformer (E 037099) that I bought off ebay.

I haven't been able to locate any information on either of these transformers though. Very frustrating. But I'm thinking it's very likely I put in an incorrect transformer as a replacement.

Problem is the reverb circuit fuzzes out way too early, around 11:00 on the reverb pan dial. I'd like to be able to crank it up even more when I want to.

I've tried swapping the 6C4 tube and I get the same result. The transformer primary is connected directly to the 6C4 plate and the reverb tank measures a low 185 ohm  input impedance.

Can someone recommend the appropriate ratio transformer I should be looking for here? Or even a suitable replacement?
 

CJ

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Jun 3, 2004
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probably a 100:1 like the Fender transformers,

a lot of amps have full reverb as soon as you turn the knob, probably a sales thing,

measure the DCR of the input to the reverb pan,  should be low ohms, other side should be higher, like 276,

maybe mod the makeup stage with a voltage divider, small  caps can be used also to tweak the tone,
 

walter

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Jun 21, 2006
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I thought the Gibson Pan and Transformer was way different than Fender, but it's been awhile since I worked on one. You might try a Fender pan as a quick fix.
 

PRR

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Jan 30, 2010
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> the reverb tank measures a low 185 ohm  input impedance.

That's a nominal 600r tank.

Fenders run 8r tank.

The get-er-done fix is to insert a stock Fender-like tank, then MARK the change on the chassis so later techs know it is changed.
 

CJ

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missed the DCR, sorry,

Mercury has them, (they have everything, but big $$)

http://mercurymagnetics.com/pages/catalog/manufacturers/MM_gibson.htm

 

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