[chargerup92]

installed new head unit with amp/two 12" sub's and two new door speakers. the trouble i am having is with radio reception when i am driving. it seems like when i turn up the volume the reception comes and goes worser. installed a new atenna assembly with mast. it helped some.rechecked the grounds and are fine. also have a 10 disc cd changer with the FM modulator control hooked up. it sounds fine when listening to CD's.
this is driving me crazy, any ideas

 

[ramchargerrunner360]

what kind of head unit is it sounds like a factory problem

 

[Slanted_Mind]

Are you running an aftermarket high-power ignition? (EG MSD, Jacobs) Are you using suppression core plug wires? What you describe sounds like ignition "noise".

-SM

 

[Ramtuff]

Do you keep the CD changer on while you're listening to the radio? When I bought my Ram, it had a FM modulated changer, and it interfered with radio reception when it was on.

 

[auwing]

Ramtuff is right turn off the changer i have a 10 disc changer in my goldwing and you have to turn it off for good recption.

 

[TaZMaNiaK]

I agree.. those FM modulators put out (from the head unit's perspective) an overwhelmingly strong signal to make sure it can take over the frequency (even if it is an active station in your area) and block out any frequencies that are close to it so there's no overlap. Usually they use 88.3, 88.7 89.1, 106.1,106.7, or 107.1 (depending on the manufacturer, of course - and if you have a choice, use the higher frequencies), and the power is very low, but since it is feeding right into the antenna lead, the signal is so strong it will "bleed" several megahertz in both directions.

 

[chargerup92]

my antenna is connected to the modulator and then from the modulator to the radio. the cd changer has a remote to turn it off with. but the antenna is still connected to the modulator. do i need to bypass the modulator when listening to the radio, hope not

 

[TaZMaNiaK]

What brand/model head/changer?? Depending on the setup, some manufacturers have the modulator as a stand-alone unit (separate power/ground from the changer) which means it is always on, and others use a modulator that has some sort of control/power leads to the changer which turn it on and off with the changer. If you have a stand alone mod, just wire an on/off switch to the power lead (not ground -- the unit is grounded through the antenna lead) and cut it when you aren't playing CDs.

Matt {peace}

 

[awyseguy]

My wife "car" does the same thing with the changer I installed in it.. If the changer is on.. the reception is terrible.. Turn it off. . and it works fine again.
Aaron

 

[Streak-O-Lean]

If the changer thing doesn't work, install one of these filters on your head unit. I have had the same problem and these work real well. I like to listen to baseball on the AM side. Interference is real bad on AM, this eliminated it totally. If the link doesn't work its Radio Shack part # 270-051. They should have these in stock.
http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&category%5Fname=CTLG%5F007%5F002%5F004%5F000&product%5Fid=270%2D051

Streak-O-Lean

 

[StandardByker88]

have you tried putting a new antenna on? i got one of those billet ones at pep boys and its shorter but gets better reception. just my 2cents...

 

[chargerup92]

taz,
my wife bought me the one wal-mart had, i believe it is the DURABRAND 10 disc CD/MP3 Changer. it has a remote to it to cut it off when not in use.
thanks for the replies guys

 

[awyseguy]

I was looking at that one as well.. Can't recall who I found was actually making them for Wal-Mart to badge; but I would try disconnecting the RF unit from the antennae lead, perhaps there's a defect that is leaving the RF modulator on, when the unit itself it turning off. Could also try disconnecting the power lead to it completely and see if it clears up. It really does sound like the behavior the RF modulators cause.
Aaron

 

[chargerup92]

by-passed the modulator today and it seems to work fine. could the modulator be bad?

 

[TaZMaNiaK]

Did you try it just disconnecting the power lead from the modulator with the antenna leads still connected? Also you said it has a remote, do you mean you have a "clicker" to turn it on and off and change discs and such, or did you mean there's a blue "remote" wire going from the changer to the modulator? Did you have to wire the modulator to power at all, or is there just connections to the changer and antenna?

Matt {peace}

 

[chargerup92]

it has a "clicker" to turn it off and on with. i left it hooked up, but just unhooked the antenna from it and ran it straight to the radio. yes, the modulator has to be wired

 

[TaZMaNiaK]

Ok, then your modulator is staying on all the time. Hook the antenna back up, and disconnect the power leads and see what happens. If it clears up, you will just need to put a switch in the power lead to turn it off when you're not using it. If if doesn't go away, the modulator is bad.

Matt {peace}

 

[chargerup92]

thanks Taz, i will try that when i get time and get back to ya