Yes as long as you pay attention to current ratings. The other method is to use two tubes one higher voltage the other lower. Then use a pair of resistors or even a variable resistor and take the exact voltage from between them.
It refers to how much current the tube can pass.
If you set your current limiting resistor to 45 mA, and the load takes 35 mA, then the series string of tubes is shunting 10 mA through them. Well below ratings.
I find 10mA to be a target minimum; prefer to run closer to 15 mA or even a little higher. More reliable striking and extra headroom for load swings (depending on your load).
If you set your current limiting resistor to 45 mA, and the load takes 35 mA, then the series string of tubes is shunting 10 mA through them. Well below ratings.
I find 10mA to be a target minimum; prefer to run closer to 15 mA or even a little higher. More reliable striking and extra headroom for load swings (depending on your load).
Maybe you already know this, but...
-Glow discharge tubes are quite inductive due to the ion transit time.
-They have an ignition delay that can vary a lot from brand to brand, depending on whether the manufacturer put radioactive material in the tube. It also varies from ignition to ignition of the same tube, and it may depend on the amount of ambient light.
-For some types and brands the ignition delay in complete darkness can be of the order of seconds, at least for the Haltron 85A2 tube that I measured in darkness a couple of years ago. I have no experience with the OA3, OB3 and OC3.
-Glow discharge tubes are quite inductive due to the ion transit time.
-They have an ignition delay that can vary a lot from brand to brand, depending on whether the manufacturer put radioactive material in the tube. It also varies from ignition to ignition of the same tube, and it may depend on the amount of ambient light.
-For some types and brands the ignition delay in complete darkness can be of the order of seconds, at least for the Haltron 85A2 tube that I measured in darkness a couple of years ago. I have no experience with the OA3, OB3 and OC3.
I didn't know about nickel-63. Tritium and paint containing uranium dioxide were also popular as radioactive primers. Tritium bonded to the getter (for tubes that have a getter) and it also produced no radiation that could pass through the glass envelope. As its half life is only 12.32 years, new old stock tubes from the 1950's may now take 30 times as long to start as when they just left the factory, because only a thirtieth part of the primer is left.
There's no way to give you any meaningful answers without knowing more about your application and a schematic of your circuit. In shunt (parallel) mode voltage regulators the current through the voltage regulator tube is only a small part of the total load current and the limiting resistor is calculated in such a way that even under the heaviest load current there's still enough current flowing in the tube to maintain regulation and not stop the discharge glow. (usually 15 to 30 mA depending on the tube ratings,etc...). In series mode stabilizers (e.g used as screen dropping elements) all the current is flowing through the tube if it is not shunted by a resistor. For voltage reference applications no current is drawn and the current through the tube is usually very small (and constant). And there are many possible variations around these three schemes. The composite characteristics of series mounted voltage regulator tubes and zener diodes, and how this hybrid assembly will perform in a typical application, is very hard to predict . Some real world experimentations will be needed but be prepared for some strange behaviour and (maybe) instability. Personally I would stay with all VR tubes, they are more reliable than zeners in a high voltage environment and looks great when displayed in an open chassis.
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