[Boatanchors] Type 83 tube as a rectifier

[W4AWM at aol.com]

IBy design, a mercury vapor rectifier tube requires a short warmup period to 
vaporize the mercury. Sometimes globs of mercury settle on tube elements when 
the tube cools at shutdown. When the tube gets hit with filament and plate 
voltage without a warmup period, a condition known as flashback sometimes occurs. 
When a low plate voltage is involved, this usually does no harm but where 
extremely high plate voltages are employed, time delay circuits are normally 
incorporated to allow a short warmup period to allow the mercury to vaporize.

73,

John,  W4AWM