This small double diode has an unusual base. The 2D13A and 2D13C were essentially identical except that the 2D13C is fitted with a conventional B5 base cap (albeit of small diameter - see exhibit 2D4A. The 'P5' side-contact base cap was, we think, a Philips special (P = Phillips?) and was also used on a few TV tubes, including the miniature MW6/2 projection tube.

Valves with side-contact base caps were widely used in Philips sets during the later 1930s but some other set manufacturers disliked them so Mullard were forced to market '-C' versions of their side-contact types.

We have no operating details for this version but the 2D13C had a 13 Volt heater at 200 mA. The is exhibit is marked heater current 0.2 Amp. The voltage / current ratings of the C variant were 140 V at 0.8 mA.

The classic envelope is 28 mm in diameter and, excluding the Ct5 base pins, is 78 mm tall.

 
Absolute Maximum Operating Conditions

Diode	Vh	Ah	Va	mAa
	13.0	0.2	200	0.8

This exhibit was last updated on 01 February 2008