A very interesting story in this radar history is how the Dutch managed to
rescue the EF50 tube, essential for these early radar receivers, to England
just hours before the Germans invaded holland.
Read here ( not my site ):
Williams and Kilburn who built the Manchester Baby (SSEM) had worked on Radar during the
Second World War.
The Store, being composed of CRT tubes uses many circuits cribbed from Radar. The machine
contains 156 EF50s
the store amplifiers which detect if there is a "dot" or a "dash" on
the face of the Kilburn-Williams tube use 4 x EF50 and 1 x EF55