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Scanner / Receiver Antennas - For discussion of any type of receiving antenna used by a scanner or receiver base, mobile or handheld.

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Old 06-18-2017, 8:10 AM
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Default NEED ADVICE on Base Antenna 400mhz Range

I recently moved away from the City I need to Monitor. I'm about 30 Miles away now and The band I need to pick up is 470-500mhz Range. I run Bearcat Trunk Tracker and Currently I'm using a Discone which is NOT picking anything up.

Questions to you :

What antenna would you recommend ?
How HIGH should I mount this up ?
Best way of tuning ?
Anything else to try and Pick up the Frequencies ?
Educate me PLEASE !
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Old 06-18-2017, 12:44 PM
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30 miles is about the fringe range for UHF. You will need a very high gain directional antenna as high as possible.
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Old 06-18-2017, 1:13 PM
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A discone is an all purpose antenna with very little gain. As muskrat39 said, a directional antenna as high as possible is your best bet. Make sure the antenna is tuned to the frequency you want to hear, as that will help, and it will likely be vertical polarization. Incorrect polarization will cancel any advantage, and the higher the gain the better. An amplifier may help, but it may also increase the noise level and distort the audio.
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Old 06-18-2017, 1:20 PM
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Previous answers ate correct. You didn't mention your land geography and would also effect height needed. Here good reading on propagation: https://en.wikipedia.org/wiki/Line-of-sight_propagation

Regards
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Old 06-18-2017, 1:33 PM
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Some other points to consider:

Use the best lowest loss coax like LMR-400. It's expensive, but worth it.

Have the connectors attached by someone who knows how to do it. You can also buy already made up coax.

Some antennas won't require tuning if ordered for the correct frequency range. Use an antenna analyzer if you need to tune.

Get the antenna as high as you can.

However, before you spend big bucks run an elevation profile between your location and the transmitter site. If there is a lot of dirt in the way, you may not be able to hear the station no matter what you do.
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Old 06-18-2017, 3:59 PM
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Excellent information Gentlemen ! I Much appreciate your knowledge. The landscape is rather Noisy between where I am and the City so my GUT feeling is maybe this will NOT work. I'm willing to go the distance if you really feel I have a shot at picking up the frequencies But spending all the time and money and we still don't know makes me think otherwise,

OK...So lets entertain another avenue, I'm not THRILLED doing it this way but how about Brodcastify ? Using the Internet to get the channel ? I don't want to Run a computer 24/7 ...so is there another way to pick up the frequency over the Internet ? I can then run a PA Amplifier and Speaker to boost the volume as a scanner would do.
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Old 06-18-2017, 7:49 PM
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For 20 bucks you can buy a 4 bay bowtie TV antenna that has 14dbi gain and it covers from 460- 900

Run rg6 and you are gold
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Old 06-18-2017, 7:51 PM
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Quote:
Originally Posted by MOTEX View Post
For 20 bucks you can buy a 4 bay bowtie TV antenna that has 14dbi gain and it covers from 460- 900

Run rg6 and you are gold
I would like one of these. Where can I find it? What name or model is it?
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Old 06-18-2017, 10:49 PM
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For what it's worth, I get reliable copy through much hilly terrain on San Jose Police in 460megs from western San Francisco, a distance of 46 miles, on my D130J discone at 50 feet up. I use Times LMR240 coax. Jusy saying, if you get that discone up high enough, you might get what you want out of it.
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Old 06-18-2017, 10:57 PM
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For UHF, a clear Line Of Sight is far more important than antenna gain--you lose more signal trying to go through terrain, foliage, and buildings than you can gain from antenna design. Get the antenna above the trees and buildings and hills first, then think about gain.
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Old 06-19-2017, 10:43 AM
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So MOTEX suggesting I try a 4 Bay TV Bowtie ? I have No trouble Trying this for 20 Bananas ! Cheap enough, BUT I'm still worried about the landscape as others point out. Do we continue to seek the antenna Route out ? Which Honestly, If it worked I would prefer this method using a conventional Scanner rather than INTERNET Based Radio.

So Lets say I go with this antenna , and GOOD Cable and connectors ... should I need to run an Signal Aplifier also ? I Noted that " Scanner Master " has this bowtie style antenna for 49.00 which I can go with that covers UHF

Suggestions ? Opinions ??
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Old 06-19-2017, 11:09 AM
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Default RidgeScan

So I Looked up LMR240 Cable, and Maybe Try and get the Discone UP HIGH ...I can certainly Try this. You say you get 46 Miles away ?? OK...maybe I can Seek out doing this before I Pull the trigger on the Bowtie ...Thanks Ridge Scan Man !
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Old 06-19-2017, 2:58 PM
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Quote:
Originally Posted by metwrench View Post
So I Looked up LMR240 Cable, and Maybe Try and get the Discone UP HIGH ...I can certainly Try this. You say you get 46 Miles away ?? OK...maybe I can Seek out doing this before I Pull the trigger on the Bowtie ...Thanks Ridge Scan Man !
Sounds good met height is the concensus here in your thread, and the 240 coax is very good 50ohm feedline.
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