is it possiable to make a homemade electron tube?

Question

just wondering

Answer 1

The MARS station manager at McClellan AFB years ago told me how they made their own tubes back in the 1930's. They used a glass tube, the plate was tin and was against the inside of the glass tube wall, the grid was a coil of wire near the filament, and the filament ran through the center of the tube. The ends were sealed with rubber stoppers, and the leads passed through the stoppers. Their problem was the melting the filament did to the stoppers. I'm guessing that could be improved upon by isolating the filament by using a different kind of wire to go through the stoppers. The tube was then taken to the neon sign maker and he would pull a vacuum on the tube with a side tube used for that purpose. If you didn't have the money for a store bought tube, you improvised.

Answer 2

It sure is. Make a filament by breaking the top off an halogen lamp. Then make an anode out of a tin can and put it in a glass tube. Melt the lamp and the tube together. Pump the air out and you have a diode.

The efficiency will be terrible as the filament is not optimised to emit electrons.

Answer 3

No reason why not. You could just kludge one together with nearly random dimensions, all the right pieces somewhere near the right places, and it would surely function. I'm saying you could adjust the values of the external circuit components to accommodate whatever performance parameters your creation ended up having and you'd have a perfectly fine electronic device. The real art and science of the golden age of vacuum tubes was that engineers used the laws of electromagnetism to calculate the physical dimensions of vacuum tube components to achieve the specified electrical properties before the tube was ever constructed.