Radio antenna causing start problems?

[Astrofac]

About ten years ago we had a new radio installed in our 1978 280 Z. They replaced the original antenna switch (which I believe allowed us to lock the antenna in a up or down position) with a new toggle switch on the side of the center console. About six years ago we had the car painted. They broke the radio antenna and replaced it and wired the antenna to go up when the key was turned on and down when the key was turned off. They removed the toggle switch. The last couple of years the ignition switch will not turn the engine over until the antenna is fully up. Most of the time the ignition will not turn over on the first try. Several attempts have to be made by turning the ignition switch off, on, off, on etc. until the ignition will finally catch. Any suggestions on rewiring the radio, ignition switch or what?

[SteveJ]

Fully automatic antennas usually have two positive wires. One is wired to a switched circuit, and the other has a constant 12VDC. The switched source is the one that signals when to raise/lower the antenna. It shouldn't be wired to the starter circuit.

How old is your battery? What is the voltage when the car is off? If the voltage is dropping from the antenna going up, it might be enough to cause the solenoid not to engage. Also, corrosion in old wiring can amplify the problem.

You could use a volt meter to check the voltage at the solenoid while starting the car. Report those readings back here. It will give us a better idea of what is going on.

Do the diagnostics first before wasting money/effort to re-wire or swap out parts.

[Oiluj]

What Steve said... Sounds more like a battery or power connection problem.

The antenna should be switched with the ACC power or by a separate switch connected to the battery.

[Shade133]

wire it back to the way it was with a toggle switch. it wont be hard to do at all, and if it were my Z id perfer it to be that way. also id do what these fellas say and check battery and connection issues, because the problem you describe usually means the battery doesnt have enough CCA to crank the starter if anything else is on (radio blower motor, antennae)

[Astrofac]

Thanks for the info. Will get back as soon as I have additional information.