I've got this crazy idea, and this seems like the audience most likely to have the clues I don't.
I can't go into much detail yet (because I'm still figuring things out, and the details barely make sense in my own head), but I have a sensor where accuracy matters. The frequency at which it responds is susceptible to creep due to changes in temperature; hotter = slower because the elements expand and vice versa . As is, I'm using transistors to amplify the signal, and then there's a feedback section. I recently started dabbling in this tube stuff, and got a crazy idea to use vacuum tubes in the circuitry to intentionally get it all good and hot, but the heat would be more consistent, and I think it would self regulate as a function of the current applied AND as the resistance of the heater filaments increases with higher temperatures.
Q1: Is that crazy?
The whole thing lives in a small unventilated and somewhat insulated box leading to:
Q2: If I were to use tube rectification (both for the DC current, but also for the heat), and a dual triode in place of the two transistors in the applicable section, would I be running into issues with too much heat? Would a single dual triode be enough heat on its own to achieve the regulatory effect I'm after?
I can't go into much detail yet (because I'm still figuring things out, and the details barely make sense in my own head), but I have a sensor where accuracy matters. The frequency at which it responds is susceptible to creep due to changes in temperature; hotter = slower because the elements expand and vice versa . As is, I'm using transistors to amplify the signal, and then there's a feedback section. I recently started dabbling in this tube stuff, and got a crazy idea to use vacuum tubes in the circuitry to intentionally get it all good and hot, but the heat would be more consistent, and I think it would self regulate as a function of the current applied AND as the resistance of the heater filaments increases with higher temperatures.
Q1: Is that crazy?
The whole thing lives in a small unventilated and somewhat insulated box leading to:
Q2: If I were to use tube rectification (both for the DC current, but also for the heat), and a dual triode in place of the two transistors in the applicable section, would I be running into issues with too much heat? Would a single dual triode be enough heat on its own to achieve the regulatory effect I'm after?
A1: I think so.
Absolutely think you will go crazy trying to harness the alleged "self regulation".
If the frequency drifts with temperature:
1) Just build an oven, heater and thermostat. That's how radio stations hit their mark.
2) Phase Lock Loop to track the frequency and work a heater to bring it back to nominal.
3) Re-think so the frequency does not matter. I can measure power-line voltage 50Hz 60Hz 400Hz or between all with the same meter.
Absolutely think you will go crazy trying to harness the alleged "self regulation".
If the frequency drifts with temperature:
1) Just build an oven, heater and thermostat. That's how radio stations hit their mark.
2) Phase Lock Loop to track the frequency and work a heater to bring it back to nominal.
3) Re-think so the frequency does not matter. I can measure power-line voltage 50Hz 60Hz 400Hz or between all with the same meter.
A1: Crazy can be good... Let's see.
1) That's essentially what I'm trying to do, but with vacuum tube heater filaments as the heating element in the oven, and voltage regulation and the tendency of filaments to increase resistance with temperature as the thermostat for the oven. In this way, multiple parts of the system are doing double duty to improve the overall system compared to the status quo.
2/3) The frequency of the sensor is, in effect, the point of the thing. Changes/non-changes are what are being tracked and detected.
1) That's essentially what I'm trying to do, but with vacuum tube heater filaments as the heating element in the oven, and voltage regulation and the tendency of filaments to increase resistance with temperature as the thermostat for the oven. In this way, multiple parts of the system are doing double duty to improve the overall system compared to the status quo.
2/3) The frequency of the sensor is, in effect, the point of the thing. Changes/non-changes are what are being tracked and detected.