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  #1  
Old 09-24-2009, 01:05 AM
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Willallison Willallison is offline
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Omni-direction TV Antenna location

I have a rather odd question for you all.
Obviously the ideal location for pretty much any antenna is as high and free from obstruction as possible. But does anyone have any experience with mounting an omni-directional tv antenna (receiving digital tv) inside? Clearly, signal strength will be 'diluted', but with a good quality, amplified antenna, is reception acceptable with the antenna inside the boat?
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Old 09-24-2009, 07:05 AM
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Hi Will, i'm not sure what your after as last directional signal i touched was satelite and no good for smaller boats
we view digital cable and: wireless digitenne tv boxes also in 12v, antenna 15cm high and works in cars boats etc € 8.50 a month for the decoder card
http://en.wikipedia.org/wiki/Digital...ial_television and http://www.dvb.org/about_dvb/dvb_worldwide/australia/ looks like DTT is just introduced there?
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Old 09-24-2009, 07:26 AM
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Originally Posted by Willallison View Post
is reception acceptable with the antenna inside the boat?

Yes, to some extend, but you know that anyway.
Richard
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Old 09-26-2009, 03:39 AM
Tim B Tim B is offline
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Signal Strength:

As with GPS and other recievers, a GRP or wooden hull will have only a slight attenuation effect. A carbon hull will have higher attenuation (as it is more conductive) and steel and aluminium will be highly attenutive (if you get a signal at all).

I have never had much luck with small TV aerials, but I'm sure it's possible to get adequate reception.

Tim B.
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Old 09-27-2009, 06:42 AM
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Thanks Tim. Yes - that's pretty much what I would expect....I've just never seen one mounted inside before, so was wondering if anyone had tried it.
Guess I'll give a try and see what happens
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Old 09-27-2009, 07:24 AM
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Aparently there is a tracking TV antenna available also, someone told me about it and it is expensive. Probably for boaters . You should also get an omni direction antenna, sorry I don't have information on either.

Maybe Google knows... ?
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Old 09-27-2009, 10:41 AM
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If you have strong transmitters within 20 km or so, a little set-top antenna should be able to pull in a decent ATSC signal, even indoors / below-decks.

My hometown is about 70 km from Toronto, so we have the CN Tower as our transmitter- even a 30 year old, analog VHF/UHF antenna with a few broken arms has no problem pulling in 40+ channels of digital TV from inside the attic.

Here in Kingston, though, we have nothing- no matter where I put the supposedly high-end indoor antenna, we get at most two fuzzy analog channels.

I've seen a few (expensive) tracking devices for satellite TV on board a boat, but so far I haven't come across any dedicated marine broadcast TV antennas. In any case, the UHF bands on which most digital TV broadcasts travel are very much line-of-sight, and at sea/lake level they will be heavily obstructed by buildings, shoreline formations, etc. The big networks have some VHF space, and thus somewhat better propagation, but if there's land between you and the transmitter, you'll probably get at least a bit of signal distortion. I suspect the slight signal degradation in 50' of coax cable will be more than compensated for by the better reception you'd get with the antenna hoisted up to the spreaders.
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Old 09-27-2009, 04:29 PM
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Originally Posted by Willallison View Post
Thanks Tim. Yes - that's pretty much what I would expect....I've just never seen one mounted inside before, so was wondering if anyone had tried it.
Guess I'll give a try and see what happens
You will pretty much see the same result as you see with a mobile phone (when we are talking digital TV only). The intrusion is sometimes impressively deep. With a standard 50€ USB stick DVBT I have a sufficient TV signal in most marinas and along the shore in northern Europe.

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Old 10-01-2009, 09:49 PM
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what sort of antenna is it?
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Old 10-01-2009, 10:12 PM
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I will be trying out a Glomex Omni-Directional antenna - their larger, more powerful unit.
Will report on my success... or lack thereof!
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Old 10-01-2009, 11:04 PM
DaveJ DaveJ is offline
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Well i was going to susjest you make a discone and hide that inside the boat, they give good performance over a wide frequencyband, good for TV, and radio's and what not. But the real question i have is, why do you want it inside???????
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Old 10-01-2009, 11:27 PM
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I'm surprised nobody has asked that yet! Mostly a matter of aesthetics, but it will also greatly simplify the installation
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Old 10-02-2009, 06:21 PM
ancient kayaker ancient kayaker is offline
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Is the TV primarily for in-marina use or on the move? If just for marina use and you are too distant from the transmitter for an omni, as is likely if you are on the coast, why not use a clamp-on a directional antenna or even a satellite dish. Put it outside if you have to; a coax doesn't need a big hole. You can tuck it away for travelling.
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