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> My Antennas > Channel Master 755
Channel Master Type 755 (75 cm) Offset Prime Focus
This
is an old Primestar antenna. I got it for
free a
few years ago,
when I found it laying face up in a drainage ditch, still attached to
the pole it was originally mounted to, alongside a country road. This
model of antenna is similar to the one above, but with an elliptical
reflector and matching feedhorn. It's still
being made by Skyware.
It was in rough shape when I found it, but still
serviceable, and gives
you an idea of how very well built these things are. It was completely
covered in mud and bugs, a thin layer of algae and general filth, and
the mount was pretty rusty. I started out by pressure washing the whole
thing, which unfortunately washed off the Primestar logo, but I do have
a template in case I ever want to paint it back on. I intended to give
it a coat of paint to make it look nice and last longer, so I scrubbed
everything with hot TSP
and a wire brush. The paint that I used is Rustoleum
Universal paint in flat black, which is
supposed to adhere well to plastic, even without a primer coat.
The reflector came out looking great. I stripped the
elevation bracket
and feed arm and repainted those in gloss gray. The original hardware
was toast, since I broke most of the bolts off trying to get them out.
I ended up just buying all new hardware. All of the bolts are just
standard parts you can find at any hardware store, except for the
elevation thing, which can be made from a hex nut and a steel spacer if
you have a welder.
Once I got everything back together it looked great.
Surprisingly, the
original LNB that came with it, an NJR single polarity model from circa
1993, still works, and has a better signal to noise ratio than a lot of
modern parts. I used this antenna for receiving the PBS channels from
AMC 21 for a while, but now I'm using it for Dish Network reception for
Echostar XVI at 61°W. The LNB I'm using with it is a CalAmp dual
output
DBS LNBF. The round feedhorn on the LNBF wasn't ideally matched to the
elliptical reflector, so I used a table saw to cut off the stock
feedhorn and replaced it with a standard UG flange, held on with JB
Weld epoxy.
You could also use a Dish Network "DBS STACKED LNB" without having to
modify it, although you'll have to insert a dielectric plate in the
feedhorn's throat.
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