Special Tubes
These "violet ray" tubes were used in various quack machines. A high voltage, high frequency signal was applied, and the argon gas inside the tube would glow. It was claimed that the violet rays would promote health. At least it put food on the table of whoever sold it. I had one of those machines a long time ago. Just a curiosity.
In this picture, the tube was fed from a small inverter which was designed to light small fluorescent tubes.
This gem is a Burroughs Beam-X switching tube. It functioned as a counter, and came out of an old Xerox machine. This was also before solid state counters were practical, but it required several regulated power supplies, and it had 26 pins in two concentric circles on the base.
It used a series of permanent magnets and electrodes to switch an electron beam. There are ten magnets inside the tube, and you can actually pick up hardware with it.
Everybody has one of these - it's a magnetron stripped of it's magnets and pole pieces. In operation, the filament is heated, and high voltage is applied to the anode. In the presence of a strong magnetic field, it will generate microwaves.
This particular tube only has it's filament. Once in a while I'll light it up. One day, a friend came over, and he started to run away when I told him what it was. I explained to him that it's harmless without the high voltage applied.
Disclaimer - Don't mess around with a microwave oven. They are far more dangerous than they may seem.
This is a photomultiplier tube (PMT). Inside the tube is a series of electrodes (called dynodes), each dynode is charged with a higher voltage than the previous one. As photrons strike the first dynode, it liberates electrons. These electrons strike the next dynode, liberating more electrons. The result is a highly multiplied (amplified) signal.
Several articles have been written on research into tubes without heaters. These devices would have the efficiency and fast turn-on times of transistors, and the high input impedance of tubes. This would be a very useful device.
Way back around 1965, Sylvania came out with the 0A5, a tube without a heater. This is the only actual one I have ever seen, so I guess it didn't get too popular.
Of course, back in the 40's they came out with the 0Z4 cold-cathode rectifier, and the BH rectifier in the 20's.
These Corotron subminiature regulator tubes from Victoreen were probably used in the KV region. I don't have any specs on them.
Of all the metal tubes made, the only one which came in a short package was the 6H6, a dual diode, the precursor of the 6AL5.
Oops. There was also the 12H6.
Oops again. There was a military type, but I only saw one, and I can't remember the type.
The 6H6 was always in a metal package.
Oops still. Here are two 6H6GT tubes. The Rogers tube has what appears to be a graphite shield, and was lifted from an old Motorola TV chassis.
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