A3 8L Radio Reception

[j4jon]

I originally posted this in the A3 section but is probably better here.

My parents have a 2001 8L A3 with the Symphony 1 HU and a Dension IceLink on the CD changer port. Recently the radio reception on MW (got it right this time) for Radio 5 is unusable, crackles and breaks up, FM is fine. I have checked that the aerial lead is plugged in to the back of the HU which it is.
Can anybody tell me if there is a seperate aerial for MW to FM and where it is?
There is a small box on top of the sub with several wires going into it, is this a diversity unit?
I have also noticed that the aerial base on the roof has some electronics in it, could this be the problem?
Somebody on the A3 forum mentioned that it may be the 'processor' in the HU does anybody have more info on this?

 

[AndyMac]

The bee-sting aerial has an amp inside the base, either this is shot or it's not getting power from the HU. FM won't be effected that badly as you can get decent reception with just a small screwdriver inserted in the aerial socket on the HU.
There's quite a few threads on here describing where the points of failure are between the HU and the aerial, but might be worth trying an aerial amp adapter just to rule out a failure in the HU powering the amp. Otherwise you'll have quite a time tracing the wire unnecessarily. Could also be the amp inside the aerial base has given up as it's quite exposed to moisture up there on the roof.
http://www.caraudiodirect.co.uk/aerial-adaptor-p-211.html

 

[j4jon]

Is it possible to measure the voltage at the aerial base to work out if power is getting to the aerial, thus eliminating either the HU (no power) or the aerial base (power)? I'm guessing it should get 12v?

 

[AndyMac]

Not easy, it uses the coax to get the 12v trigger, and do really want to remove the headlining?

 

[j4jon]

Can I not measure it in the base of the aerial itself? ie take the base off the roof so that I can measure it where the coax is soldered onto the PCB?