4 ms·
> Vacuum Tubes require high voltages to work efficiently and are not for the faint hearted. People used to build vacuum tube circuits on breadboards at home ba
by klodolph 2y ago
> Vacuum Tubes require high voltages to work efficiently and are not for the faint hearted.
People used to build vacuum tube circuits on breadboards at home back in the 1950s. They seem pretty frightening by today’s standards, but they’re a lot like big, hot, high-voltage, low-current transistors. The low-power tubes used for signals are not that hot, just kind of warm.
I’m not really criticizing here, I just want people to think of vacuum tubes as accessible to people with any kind of electronics background, and just more inconvenient than transistors.
- neuralRiot 2y agoMost people will get frightened by a medium-high or high voltage, but low voltage at high currents needs care too, a small short circuit could mean a huge fire. When I was studying we had to disassemble a decomissioned tube computer, the tubes were the sub-miniature type, the double triodes were just a bit bigger than a incandscennt christmas tree light bulb.
- deleted 2y ago[deleted]
- TheOtherHobbes 2y agoPlate voltages can exceed the skin breakdown voltage of ~450V, which potentially makes them more dangerous than a domestic mains supply.
- klodolph 2y agoStart with 150 V instead. You probably don’t need voltages that high. DIYers can stick with 200 V or something reasonable. The remaining people who deal with 450 V are probably servicing guitar amps. Plate voltages can exceed much more than 450 V. The 811A is rated for 1500 V of plate voltage. But the same is true for transistors—you can find transistors with similar voltage ratings.