The 20P1 is a purpose designed self oscillating television line output valve. It is designed to withstand a positive anode surge voltage of 6 kV and a negative grid surge of -1.5 kV. The screen grid can dissipate 5 W.
This valve would be seen in television receivers of the 1950s.
See 20P1 for the original classic envelope version. Although a more modern design, possibly for replacement use, the valve is still assembled on a standard pinch.
The wide glass tube envelope is 29 mm in diameter and, excluding the IO base pins, is 90 mm tall.
References: Data-sheet & 1040. Type 20P1 was first introduced in 1951. See also 1951 adverts.
Absolute Maximum Operating Conditions¶
Updated January 04, 2022.