[Milsurplus] PO antenna - diversity?

[William Donzelli]

OK, now I have in my van those once-mystery PO antennae (officially
CASM-66ALM). Two are packaged in a huge steel box (apparently from the
Tarawa), and one is just bobbing around (I suppose that is an extra to my
needs). The interesting thing is that they are very officially tagged as
"DIVERSITY ANTENNA".  This is what they look like: 


      XXXXXXXX XXXXXXXXX       XXXXXXXXX XXXXXXXXX
             X X                       X X
             X X                       X X
--------------------------------------------------------
|                                                      |
--------------------------------------------------------

<-----maybe 4 feet long, dipoles are close to scale---->

Now it seems to me that having two dipoles so close is not great for 
diveristy - correct? You need them to be spaced out several wavelengths 
apart, so the two dipoles don't interact. Do you suppose these were used 
in pairs, with two sets of two dipoles?

Any info would greatly be appreciated. Somehow, I think these antennae 
will just remain a curio, unless someone digs up a manual for the PO, or 
maybe even the receiver.

Also, I have not quite figured out how these mount to the ship. I suspect 
they just bolt topside, so the dipoles are aimed straight up, to capture 
the video from a circling TBM.

William Donzelli
aw288@osfn.org