electric aerial interference

[jasper]

I've had an electric aerial fitted a while ago
all works well accept that with the radio I get some crackling (no interference with cd or auxiliary input)
I have checked the earth to the aerial and all looks ok
How do I fix this ??
Thanks in advance
John

[Dave M]

Hi John
I listen to Radio 2 whilst driving for work in my Insignia and I've noticed that there has been an increase in crackling and interference on this channel, tried retuning etc but it's still there, don't know if this is the station you listen to but if it is it might not be your aerial.

[new to this]

I've had an electric aerial fitted a while ago
all works well accept that with the radio I get some crackling (no interference with cd or auxiliary input)
I have checked the earth to the aerial and all looks ok
How do I fix this ??
Thanks in advance
John

john

you fit a supressor on the arial,you get them on ebay

dave

[new to this]

Hi John
I listen to Radio 2 whilst driving for work in my Insignia and I've noticed that there has been an increase in crackling and interference on this channel, tried retuning etc but it's still there, don't know if this is the station you listen to but if it is it might not be your aerial.

dave

what are listing to radio 2 for your younger than me

dave

[Dave M]

dave

what are listing to radio 2 for your younger than me

dave

Just background music Dave, some good some bad :-)

[LAMBRETTLAD]

7 till 9.30 smooth, 9.30 till 12 Ken Bruce,12 noon till 2 smooth,2.00 till TV time Steve Wright
Can't stand the vine chap,just about tolerate Steve wright

[jasper]

john

you fit a supressor on the arial,you get them on ebay

dave

Thanks Dave I did a quick search and couldn't find much

Do you have a link to one
Thanks
John

[V Mad]

It will be a bad earth most likely. Did you test the earth with a meter?

[marshman]

You don't say if it was ok with the old aerial. If it was then as Chris says it is probably a bad earth at the aerial end. To check it you really need to disconnect the aerial lead (coax) from the radio and check that the outer is connected to the car body work using your meter. To work effectively the aerial needs a good earth connection at the base of the aerial directly to the metal bodywork, often when an aerial is swapped over this is neglected resulting in a poor signal with interference. Sometimes the crackling is in fact an intermittant earth connection to the body work as the aerial waves about when the car is going along.

Roger

[new to this]

Thanks Dave I did a quick search and couldn't find much

Do you have a link to one
Thanks
John

John

try one of these ebay 191560194670 fit it on the arial

dave

[marshman]

John

try one of these ebay 191560194670 fit it on the arial

dave

Dave, you don't fit them to the aerial, you fit them on the item causing the interference, usually the alternator or the coil. But as has been said in earlier posts you need to check the aerial has a good connection to earth, if it has you shouldn't really need suppressors, especially on an FM radio.

Roger

[new to this]

Dave, you don't fit them to the aerial, you fit them on the item causing the interference, usually the alternator or the coil. But as has been said in earlier posts you need to check the aerial has a good connection to earth, if it has you shouldn't really need suppressors, especially on an FM radio.

Roger

Roger

usually you would fit them to the coil or alternator,but in this case because its the aerial causing the trouble fit it on the aerial,

dave

[marshman]

Roger

usually you would fit them to the coil or alternator,but in this case because its the aerial causing the trouble fit it on the aerial,

dave

Sorry Dave but I can't agree with you there, putting a capacitor (suppressor) aross the aerial will act as a short circuit to the rf signal meaning little or no signal will reach the radio, which is why they work on stopping interference when fitted to other components. First John needs to check the earth.

Roger

[jasper]

Thanks for the replies gents
Iv ordered one of those suppressors
my aerial has a long metal strap fixed to the body
I wont hurt to stick another screw in it to make sure
John

[marshman]

Thanks for the replies gents
Iv ordered one of those suppressors
my aerial has a long metal strap fixed to the body
I wont hurt to stick another screw in it to make sure
John

John,

Usually the long metal strap is there to support the bottom of the aerial assembly and give it stability so that it does not stress the bodywork. It is not always connected to the aerial ground/earth. The earth bonding should be to the underside of the hole in the body where the aerial goes through. Usually the aerial comes with an "aggressive" toothed washer or similar to bite through the paint and dig into the body work. If the ground connection at this point is not good or worse intermittent then the aerial will not perform as well. So as I said in an earlier post disconnect the aerial from the radio and make sure there is a good earth connection between the coax cable and the body work at the base of the aerial. If there is then go down the suppressor route, but do not fit a suppressor to the aerial lead. Only fit a suppressor to electrical items suspected of causing the interference.

What sort of interference do you get. Is it a regular crackling or random. Carackling if not caused by the aerial tends to be more ignition/coil related, a regular whine is more usually alternator related.

Roger