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Transformer questions

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SOOooo,
I got this huge box of stuff at an auction, One Item was some kind of possible home made square wave thingy LOL
Has a 5Y3 and a 12AU7a, A few caps and resistors, And This Tranny. On the front of the unit, Theres a few binding posts, 1 Pair 285VDC 1 pair Sq Wave & 1 Pair 6.3VAC.

Heres a pic of what i have gathered from the pins on the tranny
TRANNY PINS

Without removing it, And After yesterdays fun in this POST I Figured it best not to plug this thing in as wired. ( Possibly a class project from devry technical instute of yester year)

Im Hoping to reuse the tranny in a low watt power amp, But, I cant figure out "A" the odd capacitor across line to Pin 7? and The output of Pin 8?

Then, I need to figure out a good tube to use for a 2400 ohm to 8 ohm opt. With No CT.
I have 2 of these OPT's.

I Love the AX84 guitar amp sounds Ive Heard, Thinking Just something 5 watts or so. But Single end I Guess because Im assumeing you cant use 2 of above tannys in series.

I have these Possible output tubes.
12FX5,6GC5,6AQ5,6V6GT,
And Loads of 12au7s,12ax7s for preamp.
Any Ideas?
Trout
 
The cap is to provide an AC ground for the unit, commonly used before 3-wire cords were required. From its position, the empty terminal 8 might be a center tap for the 6.3V winding.

The resistance of the windings would tell about the transformer's current capacity - very important.

6V6 or 6AQ5 would match a 2.5K transformer at 150-200 volts supply, but it would only de3liver about one watt. But if these are from a small radio or console, don't expect too much for frequency response. Again, resistance of windings might give a clue.
 
I presume you've looked at www.ax84.com

Sounds like you could almost use the thing including the chassis for one.

Just remove all the wiring and re build it according to one of the ax84 circuits, either EL84 or 6V6 would be ok, you can even use the 5y3 rectifier and power transformer if it has them in. Test it's insulation integrity first though!

For a low power single ended guitar amps, the output transformers are never very big.
 
bobhayes said:
I presume you've looked at www.ax84.com

Sounds like you could almost use the thing including the chassis for one.

Just remove all the wiring and re build it according to one of the ax84 circuits, either EL84 or 6V6 would be ok, you can even use the 5y3 rectifier and power transformer if it has them in. Test it's insulation integrity first though!

For a low power single ended guitar amps, the output transformers are never very big.

Ive started laying out the chassis, Plan is at the moment useing dual opt dual tube on a mono input.

Wiring Ect was a breeze to remove, Clearly not a tribute to the Mr Cold Solderjoint that built it. :whazzat:

Gutted the Skyline amp also, I didnt want to tempt myself trying to put an isolation tranny in. haha

As far as tubes, I havent decided on a choice of 6V6GT's or 6AQ5's the only other output tubes laying around my shops el34s,

Eh, who knows, Maybe I'll spend the 25 bucks for a fender PP tranny.
Gene
:D
 
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