Voltage doubler in the sonic amplifier

[8wattjack]

1

[sluckey]

There are several versions of voltage doublers. Can you share your schematic?

[sluckey]

It's easy. Next message you post, take a look at "Attachments and other options".

[PRR]

That is a fancy clock radio. Not only a PT, but a ground pin??

The VA load on the PT will not change much with reasonable capacitor variation. The caps are temporary storage buckets. The strain on the PT is mostly about the DC load you suck.

Too-small caps will give low voltage, but in audio (even naked pentode+OT) the ripple buzz gets bad before the voltage falls much.

Too-large caps slightly increase the peak diode current. However you have that 68r series resistor. With 60V AC the peak current can't be much over 1A cold-start, and as the caps charge it becomes much less. 1N400x diodes are ample.

If you wanted more power... but you have bigger amps.

If you want less buzz, insert 100r and say 220ufd filter between 125V source and where the 125V goes.

Why 10 Watt Pdiss? A 50L6 OT is 2K. An "optimum" current is around Vp/Rl. 125V/2K is 62mA, 7.8W. Actually most 50L6 radios and their OTs were aimed near 110V, 55mA, 6W Pdiss. Running excess current through the low-buck OT hinders bass response. Does not increase power, and may significantly reduce undistorted power below 100Hz. That can be "a sound", and no harm results. However while 10W Pdiss is legal on 6Y6, 6 or 8 W is also legal and less abuse of "a cool nos tube".

[kagliostro]

A bit more readable schematic (?)



Franco