I'm the idiot transplanting

 

Try that again - I'm the idiot transplanting the XJR into a Mark 2. After mounting the XJR electronic lock mechanisms in the Mark 2 doors and boot lid, I noticed what I think is a remote key fob antenna imbedded in the rear glass of the XJR. Since I can't duplicate that in the Mark 2 glass I need to fashon an antenna. The XJR antenna lead appears to be a traditional coaxial cable, although the ground circuit exits the cable just before the antenna connection and grounds to a stud on the tub. The antenna connection appears to be a simple snap connector with a single circuit. I'm wondering if an insulated wire connected to the antenna lead and left above the headliner would work, or if the roof sheetmetal would shield the signal? Also wondering if a tradition stubby radio antenna on the roof connected with a coax connection would work? Any thoughts would be appreciated. Here are a few pics of the hardware and circuit diagram. Many thanks.

 

Have you traced that cable to the Security and Locking Module (SLM)? If I recall correctly, the SLM antenna has a screw-on coax connector.

 

Looks like we're both correct - the control unit end is a screw-type connector and the antenna end is as I described.

 

Hopefully you've heard of these guys before... Beacham Jaguar, here in New Zealand, have done the conversion a few times, as well as putting XKR's into E-Types.
I'm sure they'll have worked out a solution to any issues you might have.
Beacham - Independent Dealer, Classic Restoration & Custom Car Experts

 

The metal would shield the antenna, but it would probably work. Just use ground the connector as it was in the other car and connect about .20 meters (8 inches) of wire to the center connector (assuming the fob is on 360 Mhz) I think i would try taping the wire to the rear glass. Or put it in the taillight assembly, it you can fit it there.

 

I believe it is 322MHZ(last three digits of the FCC ID on the back of the fob) in the US market X308. So, cut back 8.720 inches of shielding from the end of the coax cable to act as the antenna. That gives you a quarter wave antenna.

 

Thanks everyone for your feedback. Plums, as usual your insight and willingness to share is sobering, and appreciated.
Grandell, the Beacham product is what gave me the idea for this project - unfortunately they don't share the Forum's sharing ethic, and being a commercial enterprise I don't blame them. Regards.

 

BTW, you would have to also ground the shielding at the antenna end as in the original design. Just cut back less shielding, although still leaving the equivalent unshielded length of "antenna", unravel and twist into a pigtail that you can splice to a ground wire with ring terminal.

And yes you *can* duplicate the on glass antenna. Epoxy the center conductor of a coax cable to the glass near an edge, mask an antenna of the correct length extending from the conductor, paint conductor and the masked line with defroster line repair paint. Since this is glass, I suggest cellophaine tape for the cleanest edge. Remove the tape as soon as tacky to get a nice smooth edge. You will have to strip back the coax cable sufficiently to make the pigtail, then cut the center conductor to keep the unshielded part short. You could put a flag connector on the conductor so that the epoxy does not cover the side that has to contact the conductive paint. Just brush the paint right over the exposed side of the flag terminal and into the masked "antenna" line as one operation.