The NT58 valve by GEC is a VHF transmitting triode. The filament is just visible at the bottom of the anode cavity and is a spiral around the vertical rod that holds the wire and makes the return connection. The grid and anode are seen connecting to the top of the envelope by substantial supports.

The balloon envelope is 60 mm in diameter and, excluding the B4 base pins, is 140 mm tall.

 
Pin Connections

B4	1	2	3	4	tc	tc
	-	f	f	-	g1	a

 
Absolute Maximum Operating Conditions

Triode	Vh	Ah	Va	Vg	mAa	Pdiss	Pdriv	Pout	freq	f.max
	7.5	3.2	1000	-170	100	50w	6w	70W	100 MHz	300 MHz

This exhibit was last updated on 19 January 2003