Artificial heater CT for a NO heater CT power tranny!!!

5150loveeddie · Post by **5150loveeddie** » Wed Dec 28, 2005 3:47 pm

100ohms resistor to ground on each side of the heater wires would do the trick?

2watt?

novosibir · Post by **novosibir** » Wed Dec 28, 2005 3:52 pm

Yes!

0.5 watts are enough, because nearly no current there.

Larry

5150loveeddie · Post by **5150loveeddie** » Wed Dec 28, 2005 4:57 pm

Thanx Larry

scottosan · Post by **scottosan** » Wed Dec 28, 2005 5:46 pm

novosibir wrote:Yes!

0.5 watts are enough, because nearly no current there.

Larry

I've heard from a reputable tranformer maker that using the .5 watt 100 restistor can work better than a fuse in some cased of power tubes shorting out.

novosibir · Post by **novosibir** » Wed Dec 28, 2005 6:05 pm

scottosan wrote:I've heard from a reputable tranformer maker that using the .5 watt 100 restistor can work better than a fuse in some cased of power tubes shorting out.

That's right in that cases, when due to a bad or dirty tube socket any pin 3 (plate) is arcing to pin 2 (filament). If the amp doesn't have a H.T. fuse, the resistors are burning open and disconnect the way to ground, hopefully before the OT's primary burns open.

After this has happened, the amp has a huge amount of hum and then you'll know, that these resistors are fucked up - and of course one of the output tubes.

But - a H.T. fuse always is better than trust on these resistors!

Larry