About a month ago, I posted a short article to the Northwest Public Radio weblog on improving FM reception by using a decent antenna -- something that in my experience most listeners neglect. It's gotten such a good response that I'm repeating it here.
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I've been reminded recently by conversations with relatives that people are often unaware of the need to use a good antenna for FM reception. FM frequencies fall between channels 6 and 7 on your television set, so the same principles apply to FM reception as for TV reception. I received an email yesterday asking about antennas from a listener in Bellingham who is in the "shadow" of Sehome Hill from our KZAZ transmitter on King Mountain. If you're in such a "shadow" or if you live a long distance from one of our transmitters (or shorter distance from one of our translators or from a lower power station like KZAZ, KNWO or KNWV), outdoor antennas are best.
Here's an expanded version of my reply:
Antenna options depend on the radio. Most clock radios won’t accept anything other than the strand of wire hanging out the back and most boomboxes rely on a built-in telescoping rod antenna. However, more sophisticated radios will have either a pair of screw terminals or a coaxial connector similar to what you would find on a television set.
The easiest option is to get an FM “ribbon” antenna (sometimes called a “T antenna”), generally made of “TV twinlead,” at Radio Shack or Wal-Mart. They’re under $5. Make sure the end of the lead-in matches the input (screw terminals or coaxial) on your radio. You can buy them either way. The coaxial ones are harder to find, but you can easily find a 300-ohm to 75-ohm transformer (sometimes called a “balun”), also for a few bucks, at the same place. Make sure it is laid out in the shape of a T. You may need to experiment with orientation for the best reception. [Click on the image for a larger version.]
If you have a soldering iron, you can even make one out of a discarded piece of 300-ohm TV twinlead. Cut a piece that's 63 inches long. Strip off one-half inch of insulation at either end and solder the two wires together at each end. Now cut one wire in the center of this 62-inch antenna and again strip the insulation back one-half inch. Solder a random length of twinlead to this and connect the other end to your radio, following the orientation directions above.
An alternate indoor antenna is a set of TV “rabbit ears.” Extend the elements to 31 inches each and spread them out. This alternate has the disadvantage of being kind of ugly, but it works well for an indoor option.
Radio Shack and Amazon also sell small amplified indoor FM antennas for $30-$75, both on the Web only. They should work well and will definitely look better in your living room, but I haven't tried them.
The very best antenna is a dedicated outdoor FM antenna pointed at the transmitter. These are not expensive, but installation requires a helper to orient for best reception. Be careful up on your roof! An outdoor VHF television antenna is a good substitute, but beware when buying because some VHF TV antennas have a “trap” for FM signals in order to reduce interference to television stations. Make sure it's rated for FM also.
--Dennis
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