Another Power Transformer Question!

[tubedood]

Hi my friends!

Would a Weber power transformer W022772 300-0-300/330-0-330 at 100ma have enough Oommpph for a 6L6 with 2 12AX7's?

Possibly if it was a 6L6WGB/5881 type? Looks like the 6L6GC is a burley animal in comparison.

Dale

[nickb]

In a word, yes. But...

...it depends on on the circuit and operating oint. You can change the zero signal current and load impedance to give any operating point you want. If you run the 6L6 at 45mA idle and add on 5mA for the 12AX7 and another 5mA for the bean plates you get 55mA on the HV supply. To get that 55mA out of the filter capacitor will require typically 100mA RMS from the rectifiers and that equates to 71mA from the transformer for a full wave rectifier.

BTW you'll get about 450V using that transformer. 450V x 45mA = 20W. A 6L6 is max 19W, no near enough.

[tubedood]

Opps Im going to use the lil 5Y3GT rectifier sorry I didn't specify that. I could get the 120ma transformer if that is a better choice.

[nickb]

Opps Im going to use the lil 5Y3GT rectifier sorry I didn't specify that. I could get the 120ma transformer if that is a better choice.

It will be fine at 100mA. The DC current will be a little higher but the resistance of the rectifier and the small filter cap will lower the transformer Irms.