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FM Reception Distance

I have been experimenting regarding FM reception distance and antennas for full quieting in flat terrain line of sight reception. Also no local tall buildings in line with FM station signal.  FM stations are using 50KW to 100KW and have 1000 to 1500 foot antennas. An indoor twin lead antenna is ok up  to 20 miles. 7dB gain outdoor antenna is ok up to 40 miles. 12dB antenna is ok up to 70 miles with 1500 foot station antenna. 1000 foot FM station antenna is limited to about 60 miles line of site.  All have make use of a 15dB FM amplifier. Radio Shack makes a  model 15-1122 great FM amplifier dedicated to FM that is better than TV amps. The Radio Shack needs a 300 ohm o 75 ohm adapter. The FM amplifier makes a big differ3ence and especially so on lower performance J-FET FM tuners.

The FM tuner is important and needs a J-FET RF amp, Bipolar will void the reception distance above. J-FET tuners also vary in reception. The Meridian 504 is the most sensitive tuner I used. I am using a Hitachi FT-800 tuner due to best bass and clarity I  heard but a little less sensitive vs the Medidian Tuner. 

jimbennet
jimbennet OP
196 posts
 

Few FM antennas are available. DX Engineering has 8.8 to 13dB gain but the 10 dB gain antenna is $300. The Stellar Labs four element is on eBay with 7 dB gain for $59. I stacked two antennas Stellar Labs antennas for 10 dB gain and is by far cheapest option. Stacking height is 5 feet in-between antennas.

llg98ljk's avatar
llg98ljk
326 posts
 

There are also several very useful locator sites that allow you to put in your location and will show a map with coordinates of all the stations in your area. AM-FM and TV are all available to search.

livinon2wheels's avatar
livinon2wheels
263 posts
 

Hey Jim Bennet, thanks for the info on antenna spacing for a stacked array. I couldn't remember what the rule was for that, electronics school was way too long ago :) While I understand that radio is pretty much done and dead  when compared with other sources for music, for news weather and public information when the grid is down or the internet is down, hard to find fault with having radio for a backup.

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