Problem with new after market CD/Radio

[graycat]

Hello, I have a 2002 Subaru Forester and I got a new Kenwood MP228 radio/CD
player for it. However, I cannot get good reception on the AM band. One of
the strongest AM stations on the west coast, KGO 810 AM, does not come in at
all. The old unit worked just fine as far as AM reception went so I don't
think it's any problem with the antenna. The FM seems to work just fine. Am
I missing something? Any help would be appreciated.

 

[Carl 1 Lucky Texan]

Hello, I have a 2002 Subaru Forester and I got a new Kenwood MP228 radio/CD
player for it. However, I cannot get good reception on the AM band. One of
the strongest AM stations on the west coast, KGO 810 AM, does not come in at
all. The old unit worked just fine as far as AM reception went so I don't
think it's any problem with the antenna. The FM seems to work just fine. Am
I missing something? Any help would be appreciated.

Did you have the windows tinted between radios?
I also think there is an antenna amplifier that could have been left out
of the rewiring for your new unit - not certain on that though.

Carl

 

[graycat]

Did you have the windows tinted between radios?
I also think there is an antenna amplifier that could have been left out
of the rewiring for your new unit - not certain on that though.

Carl

No, I did not tint the windows.
I should mention that this is the second unit I have had the same problem
with. I exchanged it thinking it was defective, but it is obviously not.
I don't know anything about an antenna booster. The plug for the new unit
looks just like the old one.

 

[Bonehenge]

Hello, I have a 2002 Subaru Forester and I got a new Kenwood MP228 radio/CD
player for it. However, I cannot get good reception on the AM band. One of
the strongest AM stations on the west coast, KGO 810 AM, does not come in at
all. The old unit worked just fine as far as AM reception went so I don't
think it's any problem with the antenna. The FM seems to work just fine. Am
I missing something? Any help would be appreciated.

Some aftermarket radios have pitiful AM performance, it's almost an
afterthought. If you read reviews of car stereos on the web, NOBODY
ever mentions AM. I'm guessing that most aftermarket customers are
after better CD players, aux inputs, satellite compatibility, etc...
and the talk radio junkie is happy with his OEM system. The
aftermarket CD unit I put in my Wrangler has much worse AM performance
than the crappy Chrysler system that it replaced.

All that said, does your car have one or two antennas, and where are
they (or it)? Perhaps the stock unit had some sort of built-in
booster or power supply for an active antenna that's built into your
car?

Can the car stereo dealer fire it up on a test jig with another
antenna?

 

[-rick-]

Some aftermarket radios have pitiful AM performance, it's almost an
afterthought. If you read reviews of car stereos on the web, NOBODY
ever mentions AM. I'm guessing that most aftermarket customers are
after better CD players, aux inputs, satellite compatibility, etc...
and the talk radio junkie is happy with his OEM system. The
aftermarket CD unit I put in my Wrangler has much worse AM performance
than the crappy Chrysler system that it replaced.

All that said, does your car have one or two antennas, and where are
they (or it)? Perhaps the stock unit had some sort of built-in
booster or power supply for an active antenna that's built into your
car?

Can the car stereo dealer fire it up on a test jig with another
antenna?

Another possibility is that the AM antenna matching trimmer
on the new radio (if so equipped) needs adjusting to peak
the signal. AM wavelengths are very long compared to the
physical antenna and an adjustable matching network is (or
used to be) common.

Look for a small screwdriver adjustment near the antenna
input of the radio and adjust for best signal quality on a
weak station near the middle of the AM band.

-rick-

 

[Mortimer Schnurd]

Another possibility is that the AM antenna matching trimmer on the new
radio (if so equipped) needs adjusting to peak the signal. AM wavelengths
are very long compared to the physical antenna and an adjustable matching
network is (or used to be) common.

Look for a small screwdriver adjustment near the antenna input of the
radio and adjust for best signal quality on a weak station near the middle
of the AM band.

-rick-

Those went away a long time ago rick
I HIGHLY suspect there is some kind of active device between the original
equipment antenna
and the new radio that is not getting power. They are usually supplied by
the active antenna lead,
the same one that raises the antenna when the radio is on.
Due to the short whip they use now, a lot of OEM radios DO use a pre-amp
inline and its close to the
whip's location.No power to one..no signal thru it either.
Check the radio by unplugging it from the car antenna and use a 3 foot piece
of wire to see if the radio
does indeed "hear".

 

[Edward Hayes]

If your Forester antenna is in the rear window then you need to power
the hi-gain pre-amp. You need to connect the 12 volt supply to it.
Maybe others on this NG can fill in the details. Ed

 

[-rick-]

Those went away a long time ago rick

ok... If you need me I'll be out on the porch yelling at the
neighborhood kids to get off my damn lawn...

 

[Michael Pardee]

ok... If you need me I'll be out on the porch yelling at the neighborhood
kids to get off my damn lawn...

I'll be out there with you! Goldurned broadband receiver front ends anyway.
Ya know, vacuum tubes and semiconductors are both made out of sand anyway.

Mike (the old coot)