The 6217 photomultiplier was designed by RCA for applications where good red sensitivity was required. The amplification possible with the 6217 is of the order of 600,000 times and can operate linearly up to 50 MHz.

Details are scarce about the use of the 6217. It is described as a photomultiplier tube used in a BBC scanner. This suggests a role in telecine where each frame of a film is scanned by a flying spot from a cathode ray tube in a raster pattern and the transmitted light is then detected and amplified by a photomultiplier tube.

The photons striking the light sensitive target (cold cathode) release electrons that are attracted to a positively charged electrode. The electrons striking the electrode release secondary electrons and the process is repeated in a series of electrodes known as dynodes before the greatly amplified current reaches the final anode. Amplifications of up to a million times are possible with some multipliers. Early devices were sensitive in the blue and ultraviolet but not the red end of the spectrum.

The wide glass tube envelope is 50 mm in diameter and, excluding the 14 base pins, is 128 mm tall.

 
Absolute Maximum Operating Conditions

Photocell	Va	mAa
	1250	7.5

Thanks to Frank Philipse for supplying the above datasheet

This exhibit was last updated on 02 February 2008 {find valves by name}