Strange AM radio problem

[Chris]

I have an Alpine deck I bought a few years ago. For some reason the AM
radio on stations are barely audible because they are overwhelmed by
static. Yet the FM stations sound clear as bell. This problem started
happening slowly over time where would get the static occasionally,
and then the AM would be clear the next day. But now, it's at the
point where it's almost unlistenable. I don't think it would be the
car antenna since the FM seems to work fine. I hate the have buy a new
stereo head unit. What types of things might cause a problem like
this?

[Phonedude]

"Matt Ion" > wrote in message
news:Byj4g.82527$WI1.43126@pd7tw2no...
> Chris wrote:
>> I have an Alpine deck I bought a few years ago. For some reason the AM
>> radio on stations are barely audible because they are overwhelmed by
>> static. Yet the FM stations sound clear as bell. This problem started
>> happening slowly over time where would get the static occasionally,
>> and then the AM would be clear the next day. But now, it's at the
>> point where it's almost unlistenable. I don't think it would be the
>> car antenna since the FM seems to work fine. I hate the have buy a new
>> stereo head unit. What types of things might cause a problem like
>> this?
>
> It could still be the antenna - corrosion between the telescoping
> sections, or a bad ground at the base. Both would be conditions that grow
> worse over time. FM isn't as sensitive to such antenna issues.


Don't fool with it -- just replace the entire antenna assembly. They're not
that expensive. AM uses a much lower frequency range (kilocycles instead of
megacycles) and the length of the antenna is much more important. It could
be that the FM is happy with just the base of the antenna working while the
AM band wants the entire length of the antenna to be there. Again, don't
try to figure out what's wrong, just replace the entire thing. Now's the
time to upgrade to an automatic antenna!

PD

[Chris]

On Fri, 28 Apr 2006 12:00:01 GMT, "Phonedude" >
wrote:

>
>"Matt Ion" > wrote in message
>news:Byj4g.82527$WI1.43126@pd7tw2no...
>> Chris wrote:
>>> I have an Alpine deck I bought a few years ago. For some reason the AM
>>> radio on stations are barely audible because they are overwhelmed by
>>> static. Yet the FM stations sound clear as bell. This problem started
>>> happening slowly over time where would get the static occasionally,
>>> and then the AM would be clear the next day. But now, it's at the
>>> point where it's almost unlistenable. I don't think it would be the
>>> car antenna since the FM seems to work fine. I hate the have buy a new
>>> stereo head unit. What types of things might cause a problem like
>>> this?
>>
>> It could still be the antenna - corrosion between the telescoping
>> sections, or a bad ground at the base. Both would be conditions that grow
>> worse over time. FM isn't as sensitive to such antenna issues.
>
>
>Don't fool with it -- just replace the entire antenna assembly. They're not
>that expensive. AM uses a much lower frequency range (kilocycles instead of
>megacycles) and the length of the antenna is much more important. It could
>be that the FM is happy with just the base of the antenna working while the
>AM band wants the entire length of the antenna to be there. Again, don't
>try to figure out what's wrong, just replace the entire thing. Now's the
>time to upgrade to an automatic antenna!
>
>PD
>

I've never had to do this before. Does this mean just the actual
antenna on the roof itself or the wiring that runs from the antenna to
the stereo as well?

[Matt Ion]

Chris wrote:
> On Fri, 28 Apr 2006 12:00:01 GMT, "Phonedude" >
> wrote:
>
>
>>"Matt Ion" > wrote in message
>>news:Byj4g.82527$WI1.43126@pd7tw2no...
>>
>>>Chris wrote:
>>>
>>>>I have an Alpine deck I bought a few years ago. For some reason the AM
>>>>radio on stations are barely audible because they are overwhelmed by
>>>>static. Yet the FM stations sound clear as bell. This problem started
>>>>happening slowly over time where would get the static occasionally,
>>>>and then the AM would be clear the next day. But now, it's at the
>>>>point where it's almost unlistenable. I don't think it would be the
>>>>car antenna since the FM seems to work fine. I hate the have buy a new
>>>>stereo head unit. What types of things might cause a problem like
>>>>this?
>>>
>>>It could still be the antenna - corrosion between the telescoping
>>>sections, or a bad ground at the base. Both would be conditions that grow
>>>worse over time. FM isn't as sensitive to such antenna issues.
>>
>>
>>Don't fool with it -- just replace the entire antenna assembly. They're not
>>that expensive. AM uses a much lower frequency range (kilocycles instead of
>>megacycles) and the length of the antenna is much more important. It could
>>be that the FM is happy with just the base of the antenna working while the
>>AM band wants the entire length of the antenna to be there. Again, don't
>>try to figure out what's wrong, just replace the entire thing. Now's the
>>time to upgrade to an automatic antenna!
>>
>>PD
>>
>
>
> I've never had to do this before. Does this mean just the actual
> antenna on the roof itself or the wiring that runs from the antenna to
> the stereo as well?

It will depend on the type of car and the design of the antenna - you
didn't mention what kind of car this is, but if it's like most Hondas
that have the A-pillar antenna, it's simple enough: unplug from the
deck, unscrew the base, and pull the whole thing out with the cable,
then feed the cable of the new one back in the same way. You might want
to attach a string to the old one as you pull it out, and use it to help
locate the new cable when you put it in, as the opening for it under the
dash can be somewhat hidden on some cars.


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[MOSFET]

These other guys know more about AM/FM than I do, and hopefully they're
right and it's just a problem with your antenna. But I will tell you that
when I first bought my Alpine 7863 back in 2000, it DID EXACTLY WHAT YOU ARE
DESCRIBING. It started about a week after I bought it. Fortunately, it was
under warranty and it was an easy matter to exchange it from the retailer
(Car Toys in Seattle). I thought I would tell you this. However, my unit
was OBVIOUSLY faulty. Yours hopefully is not.

MOSFET

"Chris" > wrote in message
...
>I have an Alpine deck I bought a few years ago. For some reason the AM
> radio on stations are barely audible because they are overwhelmed by
> static. Yet the FM stations sound clear as bell. This problem started
> happening slowly over time where would get the static occasionally,
> and then the AM would be clear the next day. But now, it's at the
> point where it's almost unlistenable. I don't think it would be the
> car antenna since the FM seems to work fine. I hate the have buy a new
> stereo head unit. What types of things might cause a problem like
> this?

[Chris]

It's a VW Jetta.

On Fri, 28 Apr 2006 16:46:20 GMT, Matt Ion >
wrote:

>Chris wrote:
>> On Fri, 28 Apr 2006 12:00:01 GMT, "Phonedude" >
>> wrote:
>>
>>
>>>"Matt Ion" > wrote in message
>>>news:Byj4g.82527$WI1.43126@pd7tw2no...
>>>
>>>>Chris wrote:
>>>>
>>>>>I have an Alpine deck I bought a few years ago. For some reason the AM
>>>>>radio on stations are barely audible because they are overwhelmed by
>>>>>static. Yet the FM stations sound clear as bell. This problem started
>>>>>happening slowly over time where would get the static occasionally,
>>>>>and then the AM would be clear the next day. But now, it's at the
>>>>>point where it's almost unlistenable. I don't think it would be the
>>>>>car antenna since the FM seems to work fine. I hate the have buy a new
>>>>>stereo head unit. What types of things might cause a problem like
>>>>>this?
>>>>
>>>>It could still be the antenna - corrosion between the telescoping
>>>>sections, or a bad ground at the base. Both would be conditions that grow
>>>>worse over time. FM isn't as sensitive to such antenna issues.
>>>
>>>
>>>Don't fool with it -- just replace the entire antenna assembly. They're not
>>>that expensive. AM uses a much lower frequency range (kilocycles instead of
>>>megacycles) and the length of the antenna is much more important. It could
>>>be that the FM is happy with just the base of the antenna working while the
>>>AM band wants the entire length of the antenna to be there. Again, don't
>>>try to figure out what's wrong, just replace the entire thing. Now's the
>>>time to upgrade to an automatic antenna!
>>>
>>>PD
>>>
>>
>>
>> I've never had to do this before. Does this mean just the actual
>> antenna on the roof itself or the wiring that runs from the antenna to
>> the stereo as well?
>
>It will depend on the type of car and the design of the antenna - you
>didn't mention what kind of car this is, but if it's like most Hondas
>that have the A-pillar antenna, it's simple enough: unplug from the
>deck, unscrew the base, and pull the whole thing out with the cable,
>then feed the cable of the new one back in the same way. You might want
>to attach a string to the old one as you pull it out, and use it to help
>locate the new cable when you put it in, as the opening for it under the
>dash can be somewhat hidden on some cars.
>
>
>---
>avast! Antivirus: Outbound message clean.
>Virus Database (VPS): 0617-3, 04/28/2006
>Tested on: 4/28/2006 9:45:30 AM
>avast! - copyright (c) 1988-2005 ALWIL Software.
>http://www.avast.com
>
>