[Spooks] UVB-76 / MDZhB Question

[Mike Tibor]

I was just recently looking over the blog post:

http://priyom.org/blog/real-buzzer-site-found!.aspx

And something caught my attention.  Why would a transmitting station with 
a fixed frequency use a variant of a cage dipole antenna, (VGDSh) whose 
sole purpose is to increase usable bandwidth?

I would expect that from a site that might need to operate on various 
frequencies throughout a given band, but cage dipoles are sort of 
mechanically complex and have wind and ice loading drawbacks.

The only things I can think of are:

1.  The VGDSh antennas are pretty low, reflecting their NVIS
     purpose, and reducing their vulnerability to wind.  This
     doesn't explain why the use of a cage dipole design though.
2.  It could be a dual-purpose site, with transmit only on 4625,
     but receive on multiple frequencies.  This would seem very
     unlikely given the marker signal being transmitted every
     second.  Maybe the marker signal is narrow enough that it
     can easily be "notched out"?
3.  There are increased efficiencies to be had by increasing
     the effective diameter of dipole elements when close to
     ground.  This seems unlikely, but I don't really know.

I was just looking over the photos and these thoughts crossed my mind. 
I'd be curious to hear what other think of it.

Thanks,
Mike