My most recent work was in satellite b'cast TV, during which also
digitized cable TV across two countries & went through so many
attempts to do DTH in a number of markets I have lost count.
Rain fade happens as low as C-band.
Transponders are not equal.
Any dish not pointed by somebody who knows what they are
doing & with a spec-an could be as much as 1 dB down from
where it could be.
Not all STB front ends are equal & many don't even perform
per spec. Beware all first-gen DC tuner chipsets.
Dish size on the ground is always too small - despite filings
to ITU for coordination of the bird in the first place.
ODUs are almost always picked on price & there is a lot of junk
out there.
Beware mismatches on IFL if the length is short & since this
isn't AM, beware the typical slap-a-line-amp-in-there solution
for long runs.
Do not use typical CATV drop cable for IFL runs unless it is
spec'd to work at frequency range involved & even then best
to sweep it - once had Andrew replace at their cost all Heliax
IFLs at our earth station due to ringie-dingies (their 75-ohm
half-inch stuff all has this problem & not even good for 70 Mc
so it all got scrapped instead of coming home with me).
This thread has made for interesting reading, though I'm sure
somebody will tell me I don't know what I'm talking about. ;^)
73, VR2BrettGraham
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See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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