In the "Car
Radio Reception Article 1 of 2", we discussed the two
most common problems with radio reception. The first problem we noted
had to do with radio reception interference. We discussed the different
causes for this frustrating problem, and we promised to provide possible
solutions in this article. The second problem we discussed was simply
a weak AM signal. If you're not happy with the performance of your
radio, read on.
Radio Noise and Interference
The first problem we will deal with is AM radio noise and interference. You
can diagnose you car stereo reception issues as follows:
- If possible, disconnect the whip antenna in your car and start your car.
- Tune your radio to a clear, open channel without any programming and listen to the static.
- Step on the gas pedal to raise the engine's RPM.
- If you hear the same noise you heard with the whip antenna connected,
then you now know that the source of the noise is the car's electrical
system and the wire that supplies power to the radio.
- If the radio noise problem originates in the car's electrical system,
you should have your electrical connections inspected, especially
the grounds, and you may have to install a noise filter on your radio.
Now, if you didn't hear any noise with the antenna disconnected from your
car, reconnect it and proceed to the next diagnostic step:
- Start your engine again and step on the accelerator again.
- If you hear noise that increases as you step on the gas pedal or a very
high pitched crackle, the noise is actually being transmitted from
your car and being sent through the hood to your antenna.
- This is very common and the easiest type of noise to correct.
- If the car is a few years old or has a lot of miles on it, the cheapest
and most common solution is to change the sparkplug wires on your
car to original equipment or resistor-type spark plug wires. Solid
wires will cause more noise problems than you had in the first place.
- If this does not cure the problem, check your distributor cap for excessive
wear or arcing.
- Also, check the coil wire to ensure that it is not arcing.
- One of our engineers says that from his own experience, opening the hood of your
car, starting the engine, and looking around for sparks will often
help you find the source of the noise if an electrical connection
- Many people have eliminated the radio noise by having a complete tune-up
on the vehicle.
This type of noise can be reduced or eliminated by grounding the hood to the
firewall with a flexible copper strap. Unless you have a lot of experience
working with cars and radios, please leave this type of work to the professionals.
You should also check to see that the antenna's coax feedline is grounded
properly both at the radio and where the mounting bracket touches the
body (more on this in the next section). One more source of possible
radio noise is your fuel pump. Please visit http://www.arrl.org/fuel-pump-noise for
information on fuel pump radio noise -- particularly some information from Ford.
If you have your own story about solving radio noise problems, please
share it with us. We'll read any submissions we receive, and consider
them for inclusion at the end of this article.
If you are dealing with reception interference problems on your home or
office radio please visit our Radio
Noise and Possible Solutions page for a very informative
radio interference troubleshooting guide.
Weak Signal Problems
The next problem we will discuss is poor or weak AM reception. If you
suffer from poor reception and have a portable radio with much better
reception than your car's radio, the problem is most likely the antenna.
Cars are very susceptible to vibration, corrosion and other factors that
conspire to degrade the AM reception. If you have an older model car
or live in an area where conditions cause a lot of rust or corrosion,
your poor AM reception might originate at the base of the antenna or
the inside of the fender.
If you can, unscrew the antenna, and look for rust or corrosion where
the antenna attaches to your car. Removing the antenna and checking
the contact to the fender often reveals the corroded parts that might
be interfering with your radio reception. You may find that you'll
either need to replace the antenna (if it's corroded or rusted) or
go for a Full Replacement Auto Antenna. Be sure to check the coaxial cable
connector at the antenna base to see if there's excessive corrosion
at the contact point as well.
Some vehicles on the market don't have an external "whip" type antenna,
and instead, have their antennas imbedded in the glass. These antennas
typically don't work well for AM radio. We suggest installing (or paying
a professional to install) a Full Replacement Auto Antenna on the fender
of your vehicle and disconnecting the in-glass antenna. The full replacement
antennas can simply be attached to the front fender of most cars, trucks
Once you've zeroed in on the source of your car radio woes, and have gotten
that fuzzy reception back to factory specs, or better, you may want
to boost your indoor radio reception as well. Heck, you don't want
to be stuck in the car listening to the end of a talk show or a ball
game just because you know you don't get good reception inside. Fortunately,
improving indoor radio reception is much easier than tinkering with
a car. An Twin Coil Ferrite AM Antenna
will work magic for AM radio reception, while an FM Reflect
Antenna will do the same for FM. Put it all together, and you'll have the best radio
reception in town -- and won't miss a thing.
For other radio reception tips, please visit the following "What's
in the News" archived articles:
Improving AM Reception In An Office Building
FM Reception Tips
AM Reception Tips
As always, please contact us with any comments or
article suggestions you might have.