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Re: Antenna Length Calculation...was: "your mail"

Phil said:

> The ideal length is a 1/4 wavelength, minus a tad.  For VHF/FM reception, say 
> of a 93MHz station, the calculation (in metres) is something like:
> Speed of light:         300,000,000 
>                         -----------   /  4    (quarter wave)
> Frequency:               93,000,000          
> So the ideal length is around 80cm, or about 20.5 inches.  Actually slightly 
> shorter - electrons are funny things.

Ok, now your getting into my area...8-]

Actually the most accurate, easiest way to figure the length of a VHF 
antenna is to use the following formula:

2808/FmHz   ...that is divide 2808 by the frequency in megahertz. 
This gives us the length in inches. (You metric guys can extrapolate)

So, with 93.0 mHz we get: 2808/93.0 =  30.1935483871

I think it will be safe to drop most of the digits after the 
decimal...hehheh.  So, for 93.0 mHz we're talking about just over 30 

LOVE my TQ (mandatory Audi content !) 

1987 5KCSTQ
NOBGS Amateur Radio Call Sign

Kurt Wesseling
Technical Support Center
The Education Network of Maine