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Old 15th Jun 2011, 16:37
  #2068 (permalink)  
syseng68k
 
Join Date: Jun 2009
Location: Oxford, England
Posts: 297
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Did you see how they soldered WWII internal radio wiring gear, against
a/c vibration? For example, the soldering of BC348īs, ART13, etc.
Practically zero chances to fail. (Despite nearby dynamotors, etc,)
More radio . I too had a mispent youth, starting around age 11 building s/w
valve radios and well remember command sets, hro, R1155 etc. The soldering
procedure was different than that for bucket style connectors though. Wires
and parts were first fed through a hole in the tag or valveholder, before
being wrapped round the tag at least once to make a good mechanical joint before
soldering. Such soldered joints are very reliable, especially when done by a
dedicated (as they were then) and skilled workforce who took pride in doing
the job right. The inspectors even dabbed paint spot on every joint in those
days in some cases, unheard of now. The wire was often cotton covered,
cable harnessed and tied down, all of which absorb vibration quite well.
Larger components, such as caps, chokes and power resistors etc, were nearly
always screwed down to the chassis before wiring. The command sets in particular,
were beautifully lightweight engineered, with mica sealed components and
invar plates used in the tuning capacitor for stability.

In the states in 1977, flew in a DC3 between cities at one point and could
not believe it when I went up front and saw a rack full of command receivers
and associated transmitters etc, in an alcove just behind the crew. All the
black crackle paint and smell of hot valves and motors took me back several
decades ...
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