Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: mark_enger on June 03, 2009, 09:36:18 pm
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im building a small champ, the transformer im using was hooked to a 6x5gt, im wondering if i should use this recto or just use a 5y3 is this a replacment for a 5y3? mark
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Does the transformer have a 5V winding? That might make the decision for you.
If it does have a 5V winding it's really a tossup. I don't think it's going to make much difference in your sound, and I'd guess they'd drop similar voltages. If it was me and I had the 6X4 and would have to go out and buy the 5Y3 I'd run the 6X4 (really cheap NOS, too).
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Mark,
It's basically a larger bottle version of the 6X4. (Same specs even.)
Pins 3 & 5 are the plates
Pin 8 is the Cathode,
and Pins 2 & 7 are the heaters: 6.3v @ .6A
Totally different pinout than a 5Y3 (which is directly heated cathode) and has a higher working voltage too.
Pins 2 & 8 are Heater/Cathode: 5v @ 2A
Depending on your operating voltage and current draw (output tube selection) this may be OK for your intended project.
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also check out the specs. Franks Tubes is good: http://www.mif.pg.gda.pl/homepages/frank/vs.html
There are signifigant differences & limitations for 1st filter cap values for these different rec tubes. E.g. 6X5 > 4uF !!! Also check the amount of B+ voltage after rectification.
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ill look @ the cap can jjasilli it looks like 10 uf for first filter cap ya thats what they used then to the 6v6 , id just try it like fender did it but ill use the 10 uf @400 I GOT IM GONNA TRY 3 PREAMP TUBES LIKE THE ULTRA CHAMP ON CERIATONE THIS AMP HAD 3 PREAMP TUBES SO IT SHOULD WORK OUT MARK
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If the PT was made to run the 6x5gt, can you use the PT for a 5y3?, just wire the pins differently. (for a 5f2 build)
the donor Sears amp I bought was described wrong, I cut all the parts out then realized there was no 5y3 like the ad said. I wired the PT to the rect. socket as you would for the 5y3 in my Princeton build but still working on the turret board so thought I better find out if this tranny will even work.
Two yellow wires to pin 2 and 8, two red to 4 and 6 then B+ goes to the board from pin 8. That left me with One Red/Yellow, One Green, and One Black wire coming out of the PT.
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If the PT was made to run the 6x5gt, can you use the PT for a 5y3?, just wire the pins differently.
No. 6X5 requires a 6.3VAC filament voltage and 5Y3 requires 5VAC filament voltage.
Two yellow wires to pin 2 and 8,
Yellow is typically used for 5VAC winding. Unplug your 5Y3 and check the voltage between the yellow wires. If it's 5, then you're good to go.
two red to 4 and 6 then B+ goes to the board from pin 8. That left me with One Red/Yellow
The red/yellow is probably the center tap for the red leads. Check for continuity to the red leads. If it is a center tap, connect it to ground.