Any radio experts

My defender has an aftermarket radio fitted in the cubby box

Receptions always been a but crap and the aerial cables bodged onto an old cb aerial ,so I fitted a new cable and aerial and I think its worse now !

There are charging pints next to the radio ,could this be causing interference?

Do those cheap plug in signal boosters work?

Thanks

Aerial will need to be grounded, try grounding the head unit too
Is the head unit any good?

Aerial is grounded to the roof via the serated washer on the back

I can try earthing the head unit and I may have a spare to swap over to check that possibility

Thanks

it should earth through the -ve wire but earthing the body too may help
is there continuity from the roof to the chassis?

Il add that to my list of things to check

The charging points - are they usb ones or straightforward fag lighter sockets? If usb then the transformers certainly won't be helping things - they can be very noisy. Fag lighter ones no problem - until you plug in a transformer type plug!

Actually I don't think the antenna should be grounded for a receiver. Think of your portable transistor radio. Is that antenna grounded? For a transmitter you do need a ground system. I would suspect a bad connection or grounded connection. If you have a multimeter that does continuity checks you should do the following:
- the center pin on the cable from the antenna should be connected to the antenna
- it should NOT be connected to the vehicle body or the metal cap that is at the end of the cable.

Does it plug into the radio all the way?

The charging plugs should not reduce reception but the USB might introduce noise. Doubtful though.

chrisstdt said:

My defender has an aftermarket radio fitted in the cubby box

Receptions always been a but crap and the aerial cables bodged onto an old cb aerial ,so I fitted a new cable and aerial and I think its worse now !

There are charging pints next to the radio ,could this be causing interference?

Do those cheap plug in signal boosters work?

Thanks

Click to expand...

Reception when using a CB antenna is the same as using a coat hanger... poor to start with.

So whats the reception like with out the engine? If there’s interference when the engine is running then u need to find the cause and suppress it.
As for “grounding” the antenna will need to fixed tight direct to metal, if mounted on aluminium then a separate earth connection is required and that will suppress any interference picked up on the co-ax feed cable.

The head unit cage can be grounded locality, and that will or should suppress local interference, therefore charge points shouldn’t be an issue, but obviously will depend on the quality of the item and how they are installed.

Signal boosters, theres a lot of vehicles that now have them installed from the factory even my old D1 has one, cheap plugin signal boosters I’m not familiar with.

Thanks for the replys il check all that out

There is a USB and cugarvlightervtypr plug but I don't use the USB

I've found today that when I plug my phone into the cigar lighter to charge the radio gets crackly

kermit_rr said:

https://itstillruns.com/good-ground-car-antenna-5758656.html

Click to expand...

I don't believe it. Excess voltage? From where?
Please explain how a portable radio works without a ground. Even weak shortwave radio signals can be picked up on a portable.
OP should go to a radio shop and get a proper car antenna.
Noise when charging the phone is probably from the phones charging circuitry.

OP should go to a radio shop and get a proper car antenna.
When charging the phone it is probably the charging circuitry ithe phone that is causing the noise unless there is a bad 12V connection at the lighter socket which is making/breaking connection.