WA2GIN asked:
>Does anyone remember the old days of two to three TV channel reception?
>
>Does anyone remember when the local town geek who would go up to the top
>of the mountain and install two VHF antennas, one high gain antenna
>pointed toward the big city where the TV transmitter towers were located
>and one low gain antenna pointed downward toward the small town in the
>valley? He just connected the two antennas with twin lead. No power
>amplifiers (no electricity up there). This was popular back in the
>days...did it work?
This is done here at UHF for TV.
I used to live in an area where Gov't policy prevented sufficient
coverage (land grant depends on population served), so remote
villages rely on back-to-back antennas on a strategic nearby hill top.
Our UHF TV transmission system was designed such that large
antennas & pre-amplifiers are needed even line-of-sight to some
transmitter sites, so a pre-amp does need to be put between the two
antennas.
For those stringing beverages where cows roam, a village I once lived
in had a back-to-back thing set up & I looked into rebuilding it. On a
barren grassy ridge - with the occasional boulder elsewhere to rub
against - the cows ate through the cables, trampled the ammo box
housing the pre-amp & even gnawed on the antennas.
I concluded I could not make a solar panel survive, so when I couldn't
get enough fellow residents to organize a battery brigade, I got on
with making the most of the unlikelihood of TVI complaints. ;^)
For the amount of power arriving from a repeater across a known path
loss, into antenna of known gain, through cable of known loss, back
into antenna of known gain & across a known path loss, this could
work passively for a repeater & users that are sufficiently loud enough
themselves.
It is either not sexy enough or wouldn't work for us, as I would have
expected somebody to have had a go by now - our topography, lack
of repeater sites & distances involved here make this an attractive
idea.
73, VR2BrettGraham
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