This small double diode has an unusual base. The 'P5' side-contact base cap was, we think, a Philips special (P = Philips?) 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.

The balloon envelope is 29 mm in diameter and, excluding the Ct5 base pins, is 86 mm tall.

References: Datasheet & ³⁰⁰². Type 2D13 was first introduced^¶ in 1934.

 
Absolute Maximum Operating Conditions^¶

Diode	Vh	Ah	Va	mAa
	13.0	0.2	200	0.8

PDF scanned from an original document held by the museum