Car radio reception

No. VHF aerials are tuned. Change the length at random at you will probably make reception worse.

Dave

Some car aerials are amplified, I understand. An (additional) amplifier may help, perhaps.

Also, where is the aerial? Where was the aerial on your last car?

Cheers

Dave R

On roof back - last car on roof front

Not usually helpful, you amplify the noise as well. Could be the amplifier expects power from the radio and if the radio has been swapped does the new one provide power.

If you have the sharks fin thing, I don't believe that is the FM aerial. For FM its printed on a window, looks like a heater element, or actually uses the heater element.

More details, such as car make/model & radio make/model might help us suggest better solution.

Dave

Presumably it's the same car Jim asked about a few weeks ago?

Can you tell from the colour of Fakra plugs whether power is supplied to the base of the aerial?

Citroen C3 2015 VTi Mark 2 I guess it is a manufacturer installed radio. Has installed touch screen tablet radio controls, not well documented in any online handbooks. Current length is 41 cm which seems to be the most common, but supposed replacement aerials are available at 32, 28, 23, 18 and 9 cm options. Hence my original question.

:o) The chances of this 84 year-old poking about in the roof lining are zero. However the fitting on my roof does not have that 'collar' at the bottom.

If they are "Genuine" and designed to fit, you would expect best performance from the 41cm option. If you look closely these are "helical" so the actual length isn't the same as the physical length. The actual wire is coiled round a core.

The optimal straight length is around 78cms. You want a quarter wave which for VHF FM is between 75 to 82 cms. DAB is on a a shorter wave length, and medium wave is of course much longer.

I suspect the issue is that there is an amplifier somewhere which for some reason is not getting power or not working, or there is corrosion in an internal joint, or the cable has become damaged.

Dave.

Which is the most likely event! Most all of the UK is now covered well by the BBC DAB services and FM for that matter, OK excepting remote parts of bonnie Scotland then medium wave going the way of the dinosaurs!..

A car radio is normally a very good reception environment quarter wave aerial element metal ground plane most of the time out in the clear no close building screen..