[Milsurplus] Re: 3 loop antennae on Mariner

[Hue Miller]

On the Mariner photo, the first loop football is right about where the cockpt
window glass ends. The rest 2 look spaced at about 5 ft each, the third and 
last is right about at the line which would be the front of the wing. The ant.
post that supports the front of the wire HF antenna is about another 5 ft
back from this.  I dunno, maybe mail call was such an important function to
service people's morale, this PB2Y-3 had extra avionics! The photo is in
"Pacific Fleet At Play", and it's kind of a revelation that a good level of 
work and lots of money was put into recreational facilities for the Pacific
service people. Only other radio photo is of Navy folk listening to news
of VJ day  on a Hallicrafters S-20R.

I recall reading about a Bendix DF receiver that did away with the 
conventional BFO, it had an audio oscillator ( !!) keyed by the
detected RF from the IF. This might have worked well in a screened
room, but the end users apparently encountered noise on the radio
wavebands, and lo and behold, the noise keyed the audio oscillator 
just as well as any signal. So there was a modification published, to
build in a conventional BFO oscillator, after all. This was an RDF
model after the MN-26 and MN-28.

BTW, lemme ask this: with the DW loop, which is similar to the DU,
except the DU was for  use inside glassed in cockpits, and on the
DW, the long neck extended thru the plane's skin and the actual
loop was outside, how in the wind slipstream did the operator
turn the loop, and keep it in  position when seeking a null? The
mechanics of the loop wouldn't seem to be up to this.

Also, i saw a photo of some kinda PBY where it looked like a DU
control box was at the top of his big stack of radio equipment
( RU's and LM and such ). In the photo you could not see the loop,
which of course wouldn't work inside the airframe anyway. So i'm
wondering if somehow it was a model DU, with the loop outside
the plane somehow? No, that does not make sense. I better look
for that photo so i can  document that to you.
-Hue Miller