Do any of you have FM radio DX systems?
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Where can I get a 13 or larger element antenna?
Sent from my 14.4 K dialup connected IBM Think Centre
Do any of you have FM radio DX systems?
Yes, sort of. I have a rooftop TV antenna on a Channel Master rotor. TV VHF Low band is fairly close to FM radio, so it works well for both TV and FM radio.
FM radio transmitters are strong, so the main limit for reception is line of sight. I am at about 300 feet elevation and often after sunset I can pick up the San Francisco stations broadcasting from the Sutro tower about 100 miles away. The top of the tower is at 1800 feet elevation. When there is tropospheric ducting (thermal inversion) I can get San Jose which is around 140 miles (well beyond the optical line of sight).
So the elevation of your antenna and the broadcast tower are more important (in my opinion) than antenna size.
Best DXing time for FM radio is usually during summer evenings.
Yes, sort of. I have a rooftop TV antenna on a Channel Master rotor. TV VHF Low band is fairly close to FM radio, so it works well for both TV and FM radio.
FM radio transmitters are strong, so the main limit for reception is line of sight. I am at about 300 feet elevation and often after sunset I can pick up the San Francisco stations broadcasting from the Sutro tower about 100 miles away. The top of the tower is at 1800 feet elevation. When there is tropospheric ducting (thermal inversion) I can get San Jose which is around 140 miles (well beyond the optical line of sight).
So the elevation of your antenna and the broadcast tower are more important (in my opinion) than antenna size.
Best DXing time for FM radio is usually during summer evenings.
Agree on height, best time in New England seems to be late afternoon to just before sunset sometimes especially around sunset. In Florida during the twilight to very early evening.
TV channel RF6 and the FM band are literally adjacent and back in the day of analog TV, you could tune the audio carrier of RF6 on an FM radio at 87.75MHz.
There are none manufactured or easily available in North America, but there are sources overseas.
You will find a lot of information about FM DX antennas on the website of the World TV-FM DX Association (Worldwide TV-FM DX Association), particularly in their antenna forum (The Antenna Forum). The most-favoured line of FM-DX antenna designs discussed there are those by Peter Körner (up to 19 elements). There's a Swedish company that manufactures his designs (but apparently shipping to North America is rather steep). Alternatively, the designs are published for home construction. A construction guide for a 19-element is posted at FM-DX: Körner 19.3 Yagi – FMDX.pl
Be aware that such a large antenna would likely over-stress a regular antenna rotor (like a Channel Master), and require a heavier-duty Ham-grade rotor. In addition, a Yagi-Uda with a large number of elements will be very directional, so you will need the more accurate heading read-out provided by eight-wire ham rotor controllers compared the the much less accurate one used in the less-expensive three-wire rotor controllers.
I love my Sony XDR F1-HD and Channel Master rooftop antenna setup. I've read that the Sony is pretty popular with the Dx crowd.
