working in a small town with a lot of AM listener type customers is loads of fun!!!!!
LOL!!!!
I have had to trouble shoot a lot of AM noise problems; back feeding pops with use of vehicle accessories, poor reception, alternator whine, ect....I would like this post to be one in which other installers out there who have had to trouble shoot various problems with AM to post what problems they have had and how they corrected them.
I've fixed some AM problems in a few vehicles, and some I just can't figure out. I've solved some problems by using a different power source for the head unit, using a different ground, replacing antennas, ect....I wouldn't hate AM so much if I was better at trouble shooting and pin pointing problems a little faster
any info helps, thanks in advance!!!
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ELECTRONICS RUN OFF OF SMOKE, WHEN YOU LET THE SMOKE OUT THEY STOP WORKING
Have also tried power filters in some cars. I've only been installing professionally for three years. Maybe there are some vets out there they have been in this industry for a long time and have dealed with this problem a whole lot more.
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ELECTRONICS RUN OFF OF SMOKE, WHEN YOU LET THE SMOKE OUT THEY STOP WORKING
This may not be an option, but I've replaced the whole head unit at times when we have a customer with reception problems with AM or FM. This works about 95 % of the time when reception is poor. I live in a small town as well and the radio stations are about 1.5 hours away from us. Aside from different antenna masks, the problems that I found lie in the head unit's circuitry.
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Jeff
Velocity Custom Home Theater
Mobile Audio/Video Specialist
Morden, Manitoba CANADA
Most car antennas are designed for FM reception, not AM. Therefore, if there is any fault in the antenna, it will be most noteable in the AM reception. The antenna mast recieves half of the incoming signal. The other half is recieved through the ground plane. In most vehicles, the ground plane is the fender or roof. It is vital that there be no resistance from the center antenna conductor to the tip of the antenna mast. If it is a power antenna, each section of mast must also have no resistance to the center lead. The outer lead or shielding of the antenna lead must have no resistance to ground. The base of the antenna must make a perfect connection to the metal it is mounted to. There must be infinite resistance between the center and outer lead of the antenna cable (Open circuit between them). The general average length of the mast should be 30-31 inches. Any resistance in these connections will cause major AM reception and noise problems. In the case of winshield antennas, remove any window tint and make sure there are no breaks in the antenna grid. A poor ground of the antenna or the metal it's mounted to will create alot of noise on AM. FM will suffer too, but not as bad. Don't bother with antenna signal or noise boosters, because all they do is boost the problem not fix it. Don't forget to check and make sure all connectors for the antenna are clean and tight. Check the ground for the battery to the body too. There is no cure for AM static caused by overhead hydro lines or bridges. It is a normal problem due to the way AM is transmitted. If the problem is a engine popping noise that increases with engine RPM, then you may have a wiring problem with your ignition system. This is more likely to occur on FM though.
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sparky