Use Kaiju dc filiment supply on another 300B amp?

[Thermioniclife]

Hello,
Is there any reason why i could not use the Kaiju dc filament supply on an old set of 300B amps I built ages ago ala JE Labs
design. they are dual mono amps, it appears that the supply is two separate supply's on one board.
I could build one side on the circuit board and the other side on perf board, or possibly a second pc board.
I would assume(oh no, there I go again) it runs on a 6.3Vac supply, I have a ton of current available as I am only running
one 6sn7 as a driver.
I don't mind experimenting.
Any thoughts on this matter will be appreciated.
I have built a Foreplay3 and a sex amp years ago and have just ordered a Beepre kit.
should be a nice fall project.
Regards,
Lee

[Paul Birkeland]

Hello Lee,

I don't see any reason that you couldn't do this.  The board can be cut down the middle and separated with a bandsaw or carefully with tin snips.  A 6.3V/3A winding would be plenty to heat a 300B through the Kaiju DC upgrade. 

-PB

[Thermioniclife]

Thanks for the quick reply Paul,
I may just add this item to my BeePre order I placed the other day.
my drivers run on 6.3Vac and are dead quiet, however the 300B's running on 5Vac have always had an element of hum to
them. not so terrible on a pair of 86db speakers but lately when I go to sleep and dream the letters
K..L..I..P..S..C..H appear in my head.
I have been away from the hobby for about 10 years and now I have the time to get back in.
Thanks again.
Regards,
Lee

[Tom-s]

An alternative option could be Tentlabs filament supplies. Their latest version will work from the 5V tap on the PT. If your 6.3V winding isn't up for the job (powering both the 6sn7+300b).

[Thermioniclife]

Hey Tom-S
Thanks for the input, but I have an abundance of 6.3Vac current available.

[Paul Joppa]

Be aware that the 6.3v winding will be elevated to the 300B cathode bias voltage, and you'd have to disconnect the winding from whatever ground or bias voltage it has now.

[Thermioniclife]

Good to hear from you Mr. Joppa,
I can lift the C.T. from ground on the 6.3 winding.
I believe the 300B cathode is elevated to around 72v,having said that I should be within the accepted heater to cathode voltage
specs on the 6sn7 driver which is 100v am I correct?
my concern is how this may effect the noise on the driver circuit.
any thoughts?

Thanks,
Lee

[Paul Birkeland]

A little bit of heater elevation is purported to bring some noise reduction, though I have not been able to measure this. 

[Thermioniclife]

Thanks all,
I was just reviewing my BeePre schematic and see that the 6.3Vac supply is not c.t. and the driver is run on ac then the regulated 300B supply follows. That's fine with me. I do not know the topology of the Kaiju but I feel I will be Ok. I like the idea of the common mode choke on the Kaiju that is the main reason of this post.
Peace, Love and Happiness to all.

Lee.

[Paul Birkeland]

The Kaiju has three separate 6.3V windings, though it certainly wouldn't absolutely have to have that.

[Thermioniclife]

Thanks PB,
I got ya.