Antenna for Marine VHF
On 4/23/2017 8:17 PM, Jeff Liebermann wrote:
On Sun, 23 Apr 2017 20:34:31 +0100, highlandham
wrote:
It is useful to initially make the vertical radiator and radials ,say 10
mm longer than a quarter wave for the mid band frequency (somewhere
between 157 and 162 MHz).
Nope. You want to tune the antenna for lowest VSWR in the transmit
range (156.0 to 157.5MHz) and take whatever you can get in the 162MHz
receive only region. If you try to tune the antenna for the middle of
the 6 MHz split, you'll end up with lousy VSWR at both extremes where
you want to operate, and good VSWR where you're not operating.
Frank , GM0CSZ / KN6WH in IO87AT
How lousy? Enough for the transmitter to reduce power to protect itself?
Do you have SWR numbers?
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