audio-talk

Hi Simon,

What about an Aikido pentode stylee? As long as you calculate the operatiing point so that the pentode drops B+/2 then you can use the Aikido circuit.

Bit like this....

cheers,

-- Andrew

Thanks all. This is one of those case of "its more what I might need". Basically, I'm trying to add a few quid's worth of useful bits to an order to get the freebie postage. I have long suspected these sockets are all made by the same company, probably in CN. cheers and thanks again, -- An...

Are these any good, in the past I've used ones from Parts Connexion, but I'm trying to avoid an order them at the mo' as I'm saving pennies for Witham and avoiding temptation. They look the same...does anyone know if they are?

thanks,

-- Andrew

Nick wrote:
But I am still interested to see how the OTL works out.

Me too.

Perhaps its just a combo of old age and as Nick say "start up failure/bath tub curve" causing the C3g's to fali. Andrew, 6SJ7, nice but, in my humble wotnot, gm (@ 1.6) it would be even ebtter if you were to put the 6SJ7 into a couple of 5687 or 6N6P and alike and so on, Aikido-stylee or e...

C'mon Dave, where the piccies.......

cheers,

-- Andrew

Simon and I thrashed his to death, going for max gm but not for prolonged periods, as far as I know his are OK. I have a pair triode connected in my power amp driver stage been running, quite hard, for months now, without problem, touch wood. Nick says he has lost some and you have, the only common ...

That's the problem with all this old stuff, no gaurantees Bad luck Dave.

cheers,

-- Andrew

Andrew: First time out I did the calcs Oh, good, in that case, does my number make sense? Yes, well I was with you, and agreed right up until the C/W calcs. Have a break whille I go through this. You have..... Junction temperature will be equal to: TJ = TA + PD (Q[HEAT SINK] + Q[CASE-TO-HEAT SINK] ...

I hope you don't think I did the calculations when I first built one, I used Dave's method, but I guessed you wanted a bit more than "it should be ok" :-) First time out I did the calcs, now I'm not being smug here because by the third, I'd got blase, changed the circuit and thought, ah i...

Well, Nick and others will probably shoot me down for this, but for a while I've been toying with the idea of a MC valve phono. The DL103 is an ideal candidate for a step-up-less phono, because, in my opinion, the 103 lacks the ability to drive step up transformers as well as more modern designs, su...

So you got a DL103?

cheers,

-- Andrew

Time for a new phono then?

Goooo 'an you know you want to....

-- Andrew

I have now found time to rebuild the blown reg. So assuming all is OK with it, its certainly stable at close to my calculated voltage is still very noisy. However, this is just as I expected from the last test run and proves the resistor was the culprit. The other one, set to shunt close to 7mA on t...

Hi Dave, I'm sure I don't need to remind you to keep an eye on that under-rated TX, if it goes short it could make a big natsy mess and a 'orrible smell. I was recently quite impressed at the firework display a small metal film resistor made when I ran it above its thermal limit. I have a another on...