In article ,
Chris Hogg wrote:
Ah - overloooked that the wireless requirement is a must.

I think I might have had a bit of trouble getting octal valves into
the bell push ...

Indeed, but there were some very small valves available to the public in
the early 1950's before transistors came along later in the decade. I
remember acorn valves, but there was also a little triode about 3 cm
long and the thickness of a pencil, IIRC. May have been gas-filled. Both
types were used in radio controlled model aircraft.
http://www.r-type.org/articles/art-151.htm

The real problem with valves was the power supply for the portable bit.
Like the bell push in this instance.

I'm old enough to just remember valve radio mics. But can't remember what
batteries they used.

--
*After the game, the King and the pawn go into the same box.

Dave Plowman London SW
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