[citylink_uk]

Hi all,

I have recently got a 1999 MK4 Astra 1.6 8v and have noticed a bit of interference on the factory fit FM radio on most stations.

It sounds electrical so I thought i'd check the HT leads to make sure they are ok, but what is an exceptable resistance with these leads?

With the meter on the 20k Ohm setting, the first lead showed 5.20 but the rest wouldn't even give a reading, could this be a sign of a bad/decaying lead?

Any help would be much appreciated,
Rich

 

[Brooksey]

now this is interesting, i have the same issue - it did not even occur to me that it could be the HT leads.

Also medium Wave/AM is barely listenable on my car - is it the same on yours? FM is also hit and miss often with inteferrence.

I read somewhere that some problems may be attributed to the fact that the water jet for the rear wiper is integrated into the aerial fixture. I read somewhere that if you take the thing apart and clean that can help.

So I would be interested in some help here too.

 

[citylink_uk]

now this is interesting, i have the same issue - it did not even occur to me that it could be the HT leads.

Also medium Wave/AM is barely listenable on my car - is it the same on yours? FM is also hit and miss often with inteferrence.

I read somewhere that some problems may be attributed to the fact that the water jet for the rear wiper is integrated into the aerial fixture. I read somewhere that if you take the thing apart and clean that can help.

So I would be interested in some help here too.

Yes, AM/MW stations have heavy interference and this pointed me to the HT idea. I have read that leads that may have perished or internally worn may allow the electrical noise to seep through and this would effect AM/MW radio more than FM due to the lower frequencies. I don't know what sort of resistance the leads should have, but on mine one has a 5 times higher reading to the other.

Its can't be too bad though as I haven't noticed any dips in performance.

 

[alan GEH]

you might want to test the aerial amplfier in the base of the aerial

 

[citylink_uk]

A bit of an update on this one. I've traced most of the noise to the actual firing process of the engine (i.e seems to be coming from the spark plugs/HT leads). I get no interference until the engine is fired.

My Astra does also seem to be suffering from some issues with voltage as often when all of the external lights are on the internal/external lights dim on and off very slightly. The battery is quite old but I have never had any problems starting at all.

This interference is really annoying now and seems to break through as soon as the FM radio signal gets below 'perfect' even on BBC R1 & R2 and AM is wiped out completely.