"erniegalts" wrote in message
...
Much worse at AM frequencies, of course. AM band runs from around
.53 to 1.6 Mhz, or 530 to 1600 Khz. So for an AM station at 1000 KHz
or 1 MHz, the resonant length would be 75/1 = 75 metres.

One foot = 0.3048 metres, so 75 * .3048 = 22.86 feet, the length of
your resonant vertical, so if you mounted it dead center in the metal
roof of your vehicle, the vehicle would have to be 45.72 feet wide.

Oops...

You got your math backward here.. the correct computation would be 75
(length in meters) x 3.28 (feet per meter)= 246.06 feet for a 1/4 wave
radiator at 1 MHz (not adjusting for velocity factor).