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VK6BE > HDTV 12.10.11 09:06l 41 Lines 2114 Bytes #999 (0) @ WW
BID : C60096VK6BE
Read: GUEST
Subj: Re: VK6BE > Big Switch
Path: IZ3LSV<IK6ZDE<VE3UIL<VK6ZRT
Sent: 111012/0752Z @:VK6ZRT.#BUN.#WA.AUS.OC #:8100 [Boyanup] $:C60096VK6BE
From: VK6BE@VK6ZRT.#BUN.#WA.AUS.OC
To : HDTV@WW
Yes Warren, I know about the advantages of horizontal polarization over
vertical. We worked that out more than 55 years ago when I first went on
VHF. However to go vertical with these translators of our makes sense.
Firstly they cannot for eco reasons put the big towers on the hills and so
the antenna, needing only to give local coverage are just a big stick -
vertical.
I have stayed at caravan parks in our north where there is isolation and
no chance of receiving normally transmitted TV signals where there was a
tiny 1 watt TV translater which picks up distant signals using a dish and
retransmits using a mobile whip placed in the centre of the park. Worked
well but that was some years ago and the setup may have changed now..The
park where I stay now uses a whip to give broadband coverage to the
customers who carry a laptop with wifi. Some of our towns in the far north
are close to 1000 km apart which makes some things difficult.
BTW only FOX and other satellites reception is polarised here. Hams use
circular for the frequencies above 70 cms.
Cheers,
Bob VKBE
Siting of the transmitter has nothing to do with antenna polarization but
at least you answered the question. Engineers from very early on have
known that horizontal gives greater range watt for watt which is why TV
in North America started out that way and continued well into the 1980s
when it started giving way to circular. Eventually antennas need
replacement so that's what they did when the time came. Now VHF, UHF TV
and FM are circularly polarized.
Now you might want to put a bug in the GM's ear, circular not only
doesn't care about receiving antenna orientation but it also helps cut
down multipath distortions. That's why it works well in urban areas with
those ubiquitous rabbit ears and monopoles, with FM it has another clear
advantage, mobiles are vertical so they don't need two antenna bays and a
power divider on the tower.
Hmmm, something else in common here, UHF TV translators. I've seen pretty
much what you describe in Reading, Pennsylvania.
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