............... How to improve your FM reception...............

                   (A guide to good radio reception)

Some listeners do not receive FM stations well.  Occasionally a listener
will call with a complaint that their reception has suddenly and
permanently gone bad.  Here is a guide to improving poor reception or
restoring good FM reception.

                             BACKGROUND

FM  radio is much like television.  In fact the FM band is smack in  the
middle of the VHF TV band.  At the frequencies employed, 88-108  MHz,
radio waves travel in straight lines, much like a flashlight beam.  So
any object that gets between your radio's receiving antenna and the radio
station's tower will block the beam.  For best reception, your radio's
antenna should be mounted up and away from nearby obstacles.

Another characteristic of FM and TV radio waves is reflectivity. They can
bounce off objects and be deflected by them.  This gives rise  to ghosts
in your TV picture and distorted sound from your FM radio.  When you
listen to FM in a moving vehicle,  you may hear the all-too-familiar
flutter caused by intermittent reflections.  We call that phenomena 
picket fencing.  Imagine a wooden picket fence with slats going by your 
car window.  The radio waves in the air also exhibit a similar pattern 
when combined with reflections from multiple pathways (multi-path) from 
the radio tower to you.  Indeed improper placement of a stationary FM 
radio antenna could result in it being in one of those picket shadows 
yielding a permanently weak and distorted signal.

Why is reception worse here than in the city?  Well for one, we have
enormous objects that can block and reflect FM and TV radio waves.  We
call them mountains!  The land in much of rural New England is very rocky
and hilly.  And as if that were not enough, radio stations tend to be
located in or near the urban populations they are licensed to serve.  If
you live between then, in rural outlying areas, no station is near you
and very few come from the same direction.  So for proper reception you
really have to re-orient your antenna for each station.  A fixed antenna
is at best a compromise.  It will work for some stations but not for
others.

Some of our listeners are located very close to other radio station 
towers.  Those stations can overload or desensitize your radio so it will 
have difficulty picking up a more distant signal.  The best solution is a 
large, rooftop, directional FM antenna.  Called a Yagi or Beam this antenna
focuses your reception much like the reflector in a flashlight. Aiming it
away from the offending local station and towards the distant one will help. 

                  SUGGESTIONS FOR IMPROVING RECEPTION

* Treat you FM reception as you would television.

* At home, put up a good, directional, rooftop FM antenna, the larger
  the better, (they are not expensive).

* Use fully shielded coaxial cable from the antenna to the set, not
  ribbon cable, and use appropriate adapters to connect it to your
  antenna and set.

* Consider a rotor to permit you to aim the antenna at the desired radio
  station.

* Buy the largest FM antenna you can afford. In this case bigger is
  better!

* Avoid indoor antennas as they are subject to drifting performance as
  you move about the room and will pick up interference from personal 
  computers, TV's, radios and other appliances.

* The ribbon "T" type antenna that is packed with most hi-fi sets is
  grossly inadequate and will work with only the strongest local signals.

* Clock radios, portables or boom boxes without terminals for external
  antennas will not perform well at home unless you  are quite close to 
  the radio station or have an unusually  clear path to it.

* Most cable companies pay little attention to FM reception so you may
  find that it is not good on the cable.  If so, do not connect your FM
  radio to your cable system.  You can usually do better with your own
  roof top FM antenna.

* Automotive reception is very problematical due to the hilly terrain.
  Look for car radios that have mono/stereo switches. Best reception is
  in monaural.

* A few of the premium factory equipped car stereos have diversity
  antenna reception.  Only two after market car radio manufacturers
  currently offer it.  The diversity system uses two antennas on the car
  and constantly compares reception on both, switching the better one to
  the radio.  This eliminates about  80-90% of the multi-path picket
  fence distortion of a moving vehicle.

               TROUBLE-SHOOTING TIPS FOR POOR RECEPTION

* Reposition the radio and/or antenna.

* Try another radio.

* Inspect your antenna connections in back of the set and on the roof for
  looseness and any corrosion.

* Try another antenna.

* Use a battery portable radio to sniff out the source of interference.

* Use it to check out the nearby utility poles, or neighbors house, or
  your own abode.

* Turn off the power at your main service panel and again listen on your
  battery radio, did the interference stop?  If so the culprit is in your
  own home.

* Compare your reception to that of nearby  friends and neighbors.  Are
  you all having the same problem?

* Keep a log of time of day and day of week for intermittent
  interference.  This can give you clues as to who is producing the
  interference.

* If your reception has suddenly become poor, ask yourself what might
  have changed in your vicinity?

  > Did you alter your antenna connections?

  > Did you add or remove a set?

  > Did you move some furniture, especially a metal cabinet?

  > Did you buy a new appliance?

  > Is there new construction in the neighborhood?

  > Did a new radio or TV station go on the air?

  > Did your neighbor put up a new antenna, maybe for CB?

  > Has the cable company strung new lines or done any other repairs?

  > Has it rained a lot?

  > Was it icy or windy recently?

These can provide clues as to what might have changed.

                                TO SUMMARIZE

Indoor antennas of any style are inferior to large roof top Yagi style
antennas.  For best results put up an FM antenna with a rotor.

Use only shielded type RG-59 coaxial cable between the antenna and the
set.

If your set is equipped for only 300 ohm ribbon type cable, buy the 
appropriate matching transformer to mate it with  the coaxial style
cable. (Your local TV/ Electronics dealer can help get you the right
materials).

If your radio does not have provisions for an external antenna
connection, consider replacing it with a better radio that is so
equipped.

If you are plagued by interference, prepare to do some detective work.
Swap radios and antennas.  Talk to the neighbors.  Borrow a battery
radio and survey your home and the neighborhood for the source of the
problem.

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