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TT 139VA enough to 2x5881 tubes?

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Leadman:
Hello, I want to build an amplifier with 3 12ax7 preamp tubes and 2 5881 power tubes. I want the power to be higher than a Deluxe reverb, something between 30w-40w.

My questions are regarding the TT135VA toroidal power transformer. Would it be enough for this type of circuit?

The transformer has 2 300-0 windings at 150ma, each of these windings would give me a current intensity when rectified of about 110ma. By joining them I could have a 300-0-300 winding at about 220ma, this should be enough for the design I am looking for.

Are my calculations correct? or by joining the two 300-0 windings of 150ma, I would only get an extra winding of 300-0-300 at 150ma.

Thanks in advance for your help.

Helmholtz:
What rectifier circuit and type are you going to use?

Leadman:
Bridge Diode recitifer, with Capacitor Resistor smoothing:

100uf-220R-50uf-22k-22uf-15k-22uf

Helmholtz:
With a bridge rectifier the output DC current is roughly 0.6 times the winding RMS current.

Two transformer windings can be paralled for doubled current, if
1) winding voltages are identical and
2) the voltages are in phase.
Maybe Dirk can give advice regarding the wire colors for parallel wiring.
Otherwise you will need some testing to determine relative phase.

Volka:
Hello,

reading the description Voltage phase is obvious (to me) :  Sec 1: 0V green and 300V red . Sec 2 : 0V white and 300V blue.

Cheers and Merry X-Mas

Volka

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