Antenna cable .

Perseverance and patience works.

I think I got it! The centre wire was SO thin, but I was able to remove enough of the white insulator to expose just enough of the conductor to splice it to a wire I'd attached to the male bit. I'm half way through stripping some lamp cord to wrap around as an insulator. It was a toss up between doing all this or partially removing the roof liner to get at the antenna to put a new cable in! Gets me out of the house! ;)

Automotive antenna cables are generally about the outside diamater of RG-6 but..The "Shield" is about the size you'd expect. The "insulator" between the two is a tube.. and the center wire about 28GA likely enameled (or perhaps just bare) if it's enamaled use steel wool to polish the end and solder on.

Basically i'd replace the antenna assembly to get a new plug.. not that expensive if you go 3rd party.

Orion wrote:

OEM Motorola plugs/sockets are generally not designed to be removed and reused once installed.

That's what I just found out! I ended up cutting off the female plug as it could not be completely opened up to repair it. I thought I could just wire the two halves together. BUT the actual antenna wire looks like a SINGLE very thin strand of copper. I can't imagine how to strip that! Thanks for the info!

Can you post a photo of the wire?

This wire should be coax, it will have a center wire covered by an electrical insulation which is covered by a fine wire which can be braided or may be spiraled around the center wire insulation..

Like this illustration.



Another view of coax would be similar to this..



(you would not have RG-6) but what you will have is a much smaller version which should look similar in some respects.

It would be highly unusual for any vehicle manufacturer to not use coaxial wire for the antenna. The outside shield is connected to vehicle ground and helps to reduce RF noise generated from the vehicles engine and electronics from getting to the center conductor.

There are many types of coaxial cable, you may have a sub miniature size which will have extremely fine shielding and a very fine center conductor which can be a real pain in the rear to strip back.

There are some versions which use just a foil shield and a single strand of wire intertwined with the foil.. With that type, you need to remove some of the foil to get to the center conductor..

On edit..

After some noodling, the coax used for car stereos is 125 Ohm, Belden 9857, RG-93..

Data sheet can be found HERE in PDF format.

There is a picture in the PDF, the center conductor will have a little plastic strand wrapped around it, then the insulation and then a wire braid then the outer jacket..

Nominal diameter of the coax should be .405" (10.3mm)

OEM Motorola plugs/sockets are generally not designed to be removed and reused once installed.

That's what I just found out! I ended up cutting off the female plug as it could not be completely opened up to repair it. I thought I could just wire the two halves together. BUT the actual antenna wire looks like a SINGLE very thin strand of copper. I can't imagine how to strip that! Thanks for the info!

Orion wrote:
The radio failed again so I pulled the car apart and found that the problem does not appear tp be in the male plug. I can hold it and tug it any way, in and out , and the signal does not fade. My body acts as a pretty good antenna! So the problem must be in the soldering in the female part, or the way that they connect together. I can't see any way of opening it up!

OEM Motorola plugs/sockets are generally not designed to be removed and reused once installed.

You would need to buy a replacement female end and cut off the original one..

They are available HERE



Although, since you have multiple extension pieces, you could try replacing the suspect extension..

Metra sells a variety of extension cable lengths..

HERE

Of course this is assuming that the radio antenna input is not at fault which is a real possibility.

If you are sure it is not the radios fault, replacing the entire OEM antenna system with an generic aftermarket antenna and cable may be the better route which will get rid of the janky multiple extensions.

The radio failed again so I pulled the car apart and found that the problem does not appear tp be in the male plug. I can hold it and tug it any way, in and out , and the signal does not fade. My body acts as a pretty good antenna! So the problem must be in the soldering in the female part, or the way that they connect together. I can't see any way of opening it up!

In 1969 we owned a 1969 Corvette. The radio was in the front of the console and the back was angled down. That motor (350/350) created so much heat that it melted the antenna plug and shorted it out several times. Never did come up with a fix but I became very proficient at changing it out.

The car is a 2006 Mazda 6, and the antenna is in three sections with two connections, one in the C pillar and the other down by the drivers footwell. I had thought that the problem was just the connector not making good contact , but I see now that it's probably a loose connection in one of the ends, probably the male one.
Of course the antenna is working now , but the next time it goes, I'll have to pull it apart and see if I can re solder it! Thanks for all your help.

That is a standard car radio antenna plug (AKA a "Motorola" plug) used on car radios since at least the 1960s and perhaps earlier.

OEM plug is soldered in one like this..



The one the OP pictured is a solderless replacement.

I would be amazed that anyone used that anywhere else other than right at the back of the radio. Unless they really needed to extend the wire length.. Can be a problem at times since they tend to get loose over time.. You can buy Motorola plug antenna cable extensions if needed..