Thorn Model 627UThorn Model 627UThis is an eye-catching design heralding
the advent of the sixties. This example was made soon after June
1960 which is the date stamped on its HT smoothing capacitor and
sold for £21:9:3d plus purchase tax. VHF coverage is 88-104MHz.
Using six B9A valves and a printed circuit it falls into the category
where transistor technology wasn't up to the radio industries
standards but its future interconnection arrangements were. Around
this date I remember the controversy between valves and transistors.
Transistors would never catch on; how could little bits of germanium
with three legs powered by a few volts ever hope to compete with
the like of double-diode-triode-hexodes and 6L6s. I remember when
I was doing my thesis at Liverpool University, building a speech
scrambler come stereo audio multiplexer, and never even considering
transistors in its construction. I used lots of 12AX7s and 6C4s
and cut holes for the valveholders in a chassis fashioned from
a big piece of aluminium bent to shape in an enormous bending
machine somewhere in the basement of the Mechanical Engineering
Department. It must have been as late as 1969-70 that valves disappeared
from domestic radios and I recall my new Bush colour TV bought
in 1970 was one of the first all-transistor TV sets. I see in
the latest Practical TV a firm is actually buying up ECC83s. Gone
are the days when these were ten a penny and a dozen red spot
transistors cost a weeks wages. Yet in the late 50s typical computers
used transistors by the hundreds of thousands. In those days few
knew what the inside of a computer looked like except those engaged
in the defence of the realm. It took ten years before the technology
finished elbowing its way into the factories of the radio industry
and finally ousted its glass rival.
