How quickly will a UHF unit drain the main battery?

That would have to be a VERY SMALL battery....... the UHF draws less than 1 amp (in standby mode...IE: neither receiving nor transmitting). I have a little battery (7a/h) that I use to run my Versa-lite (uses 1 a/h) and it runs for about 7 hours on a full charge.

So, for the UHF to run the battery flat in 3-4 hours, the battery would need to be about a 3 a/h.

Now, considering that "most" 4x4 batteries are rated at around 500cca or better, I would say that the other respondants (who have said several days) are more likely to be closer to the money.

Roachie

I have had mine on for 3 - 4 days and that has not prevented me from starting the motor.

PeterD

Oooops My bad I meant 3-4 days, I must of had Amps and Hours only on the brain, and didn't convert to days.

Cheers