• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

identifying lamp

That looks like a Bayard-Alpert type, high vacuum ionization gage tube. The smaller glass tube gets inserted into a compression seal to the vacuum chamber, with the tip cut off. The heater/filament causes any gas near it to ionize, and produce a small ion current to the small central wire to be measured.

This could be called a P-type tube, since ions form the current with a negative voltage plate. Not too practical except for the intended use. You need a vacuum pump to evacuate it besides. I don't think it comes pre-evacuated, so running the heater will cause it to burn up. The sealed tip is just to keep dust and moisture out until use.
 
Last edited:

potok

Member
2020-01-09 5:44 pm
Thanks for your reply!
I assumed that the tube is connected to a vacuum. It seemed strange that there are no manufacturer markings. Also, I want to understand this tube represents some sort of collection interest. I think I have a platform for her to check