[Milsurplus] Mystery Antenna Base

[Hole In The Head Press]

  Can anyone identify  this (I think) antenna base? 
<http://picasaweb.google.com/BodegaSam/Desktop?authkey=Gv1sRgCOvI7eDpk66cMQ#5512139802909247218> 


It's near the the old  AAA Battalion HQ on Fort Scott, San Francisco.

It's sitting on what appears to be a base for a depression position finder,
part of an early fire control station .

Doesn't look military, but maybe from a MARS station?

Thanks,
-- 

Sam Stokes, Publisher, KG6XYZ

Hole In The Head Press <http://www.holeintheheadpress.com/>

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