The C1 is a barretter, that is a series resistance to stabilise current flow. The barretter characteristic comes from the use of iron wire. The attached data sheet has a good explanation of the barretter and its function.

By enhansing the photograph the etched wording on the dome becomes clearer showing the made in England wording.

The fine wire showing the coiled structure and the method of support by clamping the wire to metal spokes embedded into the central glass rod.

The wide glass tube envelope is 38 mm in diameter, and excluding the Ct8 base pins is 115 mm tall.

 
Pin Connections

Ct8	1	2	3	4	5	6	7	8
	-	-	-	-	f	-	-	f

This exhibit was last updated on 31 August 2008 {find valves by name}