All about electronic valves and hi-fi
Brief post of a very long experiment. Unfortunately I’d have to dig out a long list of notes, tests and simulations to get the full thing out there. Unfortunately due to constraints, this will be brief but I hope it’d be entertaining.
My friend Vyacheslav sent me for testing an 6P36S / 6П36С output beam tetrode which was used for TV horizontal deflection circuits in the old days. Here are the nice curves in triode mode:
Low anode resistance and high current capability with its 12W of anode dissipation make this cheap indirectly heated tetrode an interesting candidate for an amplifier. Let’s have a look at the triode model:
Happy to complete the triode SPICE model if someone can translate the Russian datasheet and provide me with the electrode capacitances.
Well, how will this triode perform in a simple SE configuration? With a low Ra, a 5K anode impedance OT will work well:
With just 55Vpp we can drive this valve to produce 2W @ THD=1.6% (without considering the driver distortion cancellation). The valve can be biased nicely at 55mA and 220V.
