Ariel Amplifier?

[Mike Trident]

My 75 has a VDO CD413X radio that sometimes sounds like it's a little "off channel" if you understand, it's hard to describe. It even does it when I use my FM transmitter to play music from my phone.

Today I removed the rear quarter panel to take a look at the amp. First I tried the power lead, yes it is live. I then tuned the radio to a very weak station and connected and disconnected the power lead to see if I could notice a difference, yes I could. So it would appear that everything is working as it should. So am I still getting a weak signal? can I fit a secondary aeriel amp to boost the signal even more? Or is my radio at fault?

Thanks in advance.

Oh yes just one more thing, there are some green coloured metal spring clips that hold the rear quarter panel in place, one of mine is now missing. Does anyone know where I can buy some more?

[SD1too]

Originally Posted by Mike Trident

My 75 has a VDO CD413X radio ..

Is that radio the original factory fitment?

.. I removed the rear quarter panel to take a look at the amp.

Was the panel which you removed on the NS or OS? Was the part number on the "amplifier" XUC 100741?

Simon

[Mike Trident]

Hi thanks for answering.

Yes the radio is standard Rover fitment.

it is the N/S rear quarter panel, and yes that is the fitted amp.

[SD1too]

OK Mike, thanks. It's time for me to ask what you mean by "sounds like it's a little off-channel".

• Is it out of tune, i.e. sibilant high frequencies and the onset of distortion?
• Do you have to turn up the volume and the reproduction sounds thin?
• Are the BBC national FM stations affected?
• Is the sound quality from an audio CD normal?

Simon

[Mike Trident]

It would appear that playing about with the aeriel amp seems to have fixed the problem. Bad connection perhaps?

Driven it quite a few miles today without any problem

Thanks

[Mike Trident]

Well i tried it again today, and nope it's still not right!

My wife can hear it too. It's like there is a ssshhh added on to the end most words and sections of music.

any ideas anyone?

[SD1too]

Originally Posted by Mike Trident

It's like there is a ssshhh added on to the end most words and sections of music.

That sounds like the sibilance I mentioned earlier. That usually occurs if the radio isn't quite tuned into the station properly. You could try tuning manually to a station to see if you can eliminate it.

On the other hand it could be something like a faulty tweeter, which I why I asked the other questions in my last post.

Simon

[Duotone]

Something else to check is the aerial filter, located on the off side D pilar.

The filter sometimes suffers from faulty connections.







Also the connections from the aerial amp to the radio elements in the rear window should be checked.



Dave T

[Mike Trident]

All the connections at the rear end of the car are good. Today I tried a CD, no problem with sibilance.

I then removed the radio and unplugged the aerial lead. I noticed that the center pin of the lead had no chance of actually touching the metal in the rear of the radio. I cut up a bit of copper wire and pushed some strands into the center of the radio plug so that when the lead was pushed back on at least there would be some actual physical contact. This seems to have helped no end. I tried manual tuning to different stations and it seems to have fixed the problem, however I have been here before lol.

I retuned the radio to my FM converter so that I can play my mobile phone through it. It sounded very clear, but then I entered the sound section of my phone and played around with the sound output for a few minutes. I found that with the sound set to "tube amp" which calms down the high frequencies somewhat, I ended up with a lovely sound and no sibilance that I can hear.

Time will tell lol