On Thu, 19 Jan 2012 08:59:04 +0000 (UTC), "Geoffrey S. Mendelson"
wrote:

Jeff Liebermann wrote:

Note the C-Band DBS dishes may have holes in the mesh, but the mesh
itself is solid sheet metal.

Long ago and far away, I had one of those. It was not made of mesh, it was
made of a piece of sheet metal that had been perforated. The holes have to
be exact, besides the problems Jeff mentioned, they have to be small enough
and properly spaced that the dish still acts as a reflector at the frequencies
desired.

That's why Ku band (10gHz) dishes are usually solid. The mesh would have to be
very fine and precise.

Ummm... 10GHz is X band and DBS Ku band is 13Ghz. There are a few
wire mess and/or perforated sheet metal dishes available for DBS
satellite TV.
http://i01.i.aliimg.com/photo/v1/475037631/KU_BAND_75CM_SATELLITE_MESH_DISH_ANTENNA.jpg

The holes are not there to make it cheaper to produce the dishes, they are
to reduce weight and wind loading. I assume in colder climates they are
also there to reduce build up of rain water or snow.

Nope. There are black teflon coated dishes for that. Some have
heater wires imbedded in the fiberglass reflector. Also radomes. The
problem with ice and mesh is that the mesh is generally weaker than a
solid dish. Once encrusted with ice, the mesh might rip, bend, or
tear.

Here in Jerusalem we have snow storms every 4-5 years. The last one was
enough that the snow caused our satellite dish to malfunction, which was
not welcomed by two kids stuck at home. Due to the rarity of the snowfalls,
the hilly terrain and the warm temperatures, schools just close for the
day of the storm and then reopen the next day after it has all melted.

Paint it with glossy black paint. I did that to some white fiberglass
antennas. The ice just slides off the antenna once the sun appears.
It's not a total solution, but it helps.


--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558