WF* Television Camera tube type F9M3

This Riesel or Rieseliko tube is a miniture Image Iconoscope.

Kia Ludwig writes:- "Rieseliko" was a bit of slang. The full word was "Rieselikonoskop"
and would translate to "dripple iconoscope".

The name refers to a mechanism to eliminate the effects from secondary electrons: Directing a very slow compensation stream to the plate, let electrons dripple onto it.

This design had some fans in whole Germany. In their opinion the picture quality of the Rieselikonoskop was superior to the IO, so these tubes should still be considered for studio use and the IO, with its greater sensitivity, rather for outside broadcasts.

* WF = Werk für Fernmeldewesen