01///I a#39;Fill CATHODE CONTROL GRID I . // , 1, IIII \\\ 1/ //11 l ILa#39; \As I \ Fig. ... In general they are used in circuits where an automatic (or manual) control of circuit gain is desired, by changing the control-grid ... area cathode (which is coated with suitable emitting material such as barium or strontium), a small diameter rod- shaped pointed anode, and a starter anode. (See Fig. 3.46(f).) These elements are enclosed in an envelope containing a gas such as helium, acetylene, argon, or neon.
|Title||:||Radio Operator's License Q & A Manual|