[Milsurplus] Re: SCR-274-N Transmitter Dial (really Etc.)

[Hue Miller]

> There may be other reasons for not transmitting in hangers.> > These planes were fueled by gasoline and a spark could ignite it. Before jets,> when a ground crew came out to refuel a plane, the first thing they did was> attach a grounding lead. Enclosed spaces, like a hanger or hanger deck could well> have gas fumes.> > Another reason not to transmit is ordinance. Some explosives are set off by> electrically fired blasting caps. Remember those signs near construction sites,> saying "Turn Off Two-Way Radios"? A blanket no transmitting in hangers makes> sense in this regard too.> > As to the detuning issue, any fixed (non-trailing) antenna is far closer to the> plane than any hanger structure, (C=eA/d) so I think the hanger effects would be> second order, and only a touchup of the roller-ductor would be needed once air> born.> > FWIW,> -John
I'm sure those considerations are valid. A 15-20 foot wire when operated in the
range of 3 MHz will develop substantial voltage. I'm sure many of us got white
spots on our fingers verifying this.
However, on a single place plane or plane with no radio op, you have to maximize
the antenna current and leave it at that. Below decks on a flattop in the repair area
or such, you can imagine the capacitive effect would be much more than in an aircraft
hangar, at least the usual fixed-base hangar.
With the RU receiver, i can see that tuning up the transmitter by chart or by last logged
-notated setting would be no problem, as the RU's effective receiving bandpass is maybe
100 kHz or more. How about with the ARB ?  I talked with a man, Donald R. Blaney, who
was a radio-gunner flying off the Gambier Bay, sunk at the battle of Leyte Gulf ( i think
that's where, without looking it up right now. )  He told me he went out to the TBM and
crawled in and lissened to Tokyo Rose. I always wondered what the pilot's or radio op's
procedure was to retune to the mission's operating frequency. Did someone lug around
an LM ? But now i recall also - he told me they practically never used HF ! In fact i think
he told me only for CW practice (in the air) (but NOT in war zone)  and also, as a resource 
in case a  (enemy) contact report needed to be made at distance.  ( The figure he gave
when i asked about the ATC/ARB distance range, was as far as i remember 400 miles -
maybe he based that on the distance out of the patrols? ) 
( Flying off the Gambier Bay that last time, the planes had to take off in haste  without
 being armed. They dove at the Japanese ships just to try to distract them from firing 
at the US ships. Every calibre of gun on the Japanese ships was being fired at the planes. )
-Hue  K7HUE 
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