The CM17 photocell is probably an early design, based on the screw connector to the cathode. The cathode is a plate bent at 90 degrees and mounted so that the incident light hits the cathode at 45 degrees to each face. This structure increases the surface area of receptor for a given aperture size. The anode is a square of wire placed at the edges of the receptor aperture.

The classic envelope is 35 mm in diameter and, excluding the B4 base pins, is 95 mm tall.

This exhibit was last updated on 08 August 2006