audio-talk

I use http://www.dvdflick.net/

certainly seems likely, other thing to check is the rectifeirs feeding the caps, though if one of them had gone short, I would expect the mains transformer to complain.

I was looking at bluebells site, I think the 124D interstage could well do the job.

Seems likely if they are 600v diodes.

Ebay: 200278042473

Or

http://thetubestore.com/nos-6ck3.html

Ebay: 200278042473

Nice, looks neat enough to me!!

Might be missing something. but if you have a LC supply generating 350v that would need something like a AC input of 388v, so if you have a 388-0-388 tx, with full wave rects as you have described, then isn't each diode across the full secondary of 776v or 1080v at startup. Or at least with the cath...

If I have the numbers right, output impedance for a common cathode amplifier is RL || ra where || in parallel with. If the cathode is unbipassed, the anode resistance is increased by ra' = ra + RK( 1 + µ ) Richard, the choke size matters, as the anode resistance of the valve forms a RL high pass fil...

No, the cathode resistor would need to be the same value as the anode one.

Graeme wrote:They will be when its finished

The hum was a prediction rather than a reality

In that case my suggestions are a prediction as well

At the moment i have nothing between signal and grid (ie capacitors) is that good ?

Its not bad

Check the earthing. Are the relays being fed with a clean DC supply?

It could be, but the sheet Max was refering to talked about grounding one pin, and the answer was based upon that.

I guess the diodes are to prevent back EMF, but nt sure if they are needed here, they are normally used to stop killing a transistor driver, but as this is driven by a switch not sure about the point. I didn;t use them, low voltage signal diodes are fine. I would not bother with a resistor, just use...