Antenna Connection

What scanner to buy? What's the best antenna to use? Programming? Ask here!

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auntys_eyes
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Antenna Connection

Post by auntys_eyes »

OK, before i get howled down for asking a stupid question, i know this will sound unorthodox. I know there are better ways to achieve a better result, but all i am after here is some personal opinions as to whether the idea i have is feasable. So with that in mind, here goes nothing :lol: .

If i was to connect my hand held scanner to a standard roof mounted television antenna (via a wall mounted N-type connector to the scanner's BNC antenna in), could i expect to get any better reception indoors than with the supplied small whip antenna :?:
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VK6ZMS
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Post by VK6ZMS »

A TV antenna is directional and has a set bandwidth. ... In English, most TV antennas point away from Perth and into the hills. They are only good for 200 & 500 Mhz.
If you live in the western suburbs and beam across Perth it may work.
If you live in the foothills it would be hit and miss.
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Post by Nick »

Plus the tv antenna is horizontally polarised. The signals you are after are vertically polarised. There will be significant signal attenuation because of this difference as well as the fact it will be pointing in the wrong direction. Most properly installed TV antennae cover 45mHz through to nearly 860mHz(Channel 0 through to Ch 68). If you were to mount one vertically (turn on it's side) and fit a rotator you would find you have a good long distance antenna.The fact it is 75 ohms will have little effect on the performance as you only receiving. This will be something to think about in the future when the Metro network closes you will still be able to listen to the Major country networks.
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Post by VK6ZMS »

The driven element on a 50mhz antenna would be about 3 meters long :wink:
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Post by Nick »

There is a difference between bandwidth and resonance. Which is the reason tv antennae rarely follow conventional Yagi designs and have shorter elements between them
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Post by auntys_eyes »

Thank you gentlemen for your informed responses. I am therefore going with the "silly idea" scenario :lol: .
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Post by Zebedee »

Ah well, if you don't ask, you never find out :)
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