29-06-2020, 02:20 PM
While I was writing that I thought of the battery idea, but really went over the things I have done which may be useful. It's an approach I have not used but is in the back of my mind.
With my heater supplies I always use DC even though it may be less efficient. With these rapid heat valves I would wonder about induced hum from the direct filament anyway. Clamp diodes do seem a good idea as it's likely, at least during experiment, that more valves are wrecked through accidental HT on the filament than any component failure. I know I have destroyed at least one. When I was thinking about the capacitor it was perhaps more in relation to my HT supplies I once used to make. I used to make parallel fed multipliers with high(ish) voltage electronic smoothing and regulation. There I may be talking of a couple of hundred volts per stage so a capacitor failure would maybe have catastrophic consequences whereas my current thinking on low voltages should be far easier to sort but good thinking - thank you.
Tracy
With my heater supplies I always use DC even though it may be less efficient. With these rapid heat valves I would wonder about induced hum from the direct filament anyway. Clamp diodes do seem a good idea as it's likely, at least during experiment, that more valves are wrecked through accidental HT on the filament than any component failure. I know I have destroyed at least one. When I was thinking about the capacitor it was perhaps more in relation to my HT supplies I once used to make. I used to make parallel fed multipliers with high(ish) voltage electronic smoothing and regulation. There I may be talking of a couple of hundred volts per stage so a capacitor failure would maybe have catastrophic consequences whereas my current thinking on low voltages should be far easier to sort but good thinking - thank you.
Tracy
