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Hi I see you have set the tubes in full class a.
The current is nearly as large as the total power of the tube.
I had a bit of the data translated from Russian and saw that there are about 3 mA (270mV) at rest.
I also had a schematic with the preference for class b
with a negative grid voltage (this shouldn't be a problem the tube is capable of running at 150 v max).
And without the capacitor (it can slow down the tube a lot
and create compression).
Because it's a HF tube it's better to limit the hf with a capacitor(250v) and a resistor (the induction on this point can create a voltage of 240v)
I must say that I have not tested it.

By the way, thanks for the effort.
I'm still in a move but get to work with it as soon as possible.[/img]

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Here are some curves, from the 1981 Russian receiving tubes manual by Katsnelson and Larionov (I forgot I had these until I went looking)



From these curves, even Class B should only need -6V bias, and anything up to about -3.5V will net decent linearity in class AB. In fact, I was aiming at class AB when I came up with my resistor values, but the tubes I have are weaker than these indicate - at best they make 9.5mA plate current at 120V plate and screen, -2V bias. Hence they do run in class A. I'm not really that concerned, as efficiency is not a primary goal for me, nor power output.

The filter across the transformer is a good idea. I was having RF issues (although it may be due to layout problems). Will give it a shot.

Thank you, that I had not.
I have read on a russian forum that only one third of the power remains when used in low frequency (0.33 W X2)
No problem for me.
I'm going to use them in a stereo guitar amp, with a class D output stage.
lightweight, realistic distortion (without my socks blown off),and the possibility of a clean effect loop.
the gain stage with 6N17B-T because the combination of
triode / pentode can bring a nice distortion.
My experience is that a square wave sounds more crisp with a fast pentode.
the capacitor creates a slower rise and shoot at the top of the square wave.
This creates a lot of un even harmonics (just like even harmonics in a triode).
By the way forgive me my bad (Google) english but languages have never been my strong point.

nyazzip wrote:where is a good source for decent clip leads? ...

mini-grabbers made by Pomona. They have 300V rating but will do at least double that. The "mini" is just slightly to small to hold to a pin on an octal tube but clips well to a 9-pin or even to the lead of a standard 1/4W resistor. Very secure hold. I must have 50 of them.

http://www.pomonaelectronics.com/pdf/d3925_k4176_k5522_1_01.pdf

This should work
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