On Thu, Dec 1, 2016 at 2:59 PM, james soto via Topband <
topband@contesting.com> wrote:
> i proceed to disconnect the radials from the groundrod and just leave the
> ground portion of the coax attach to the ground rod and the reading wasSWR
> 1.2 and 50 ohms. are this normal ?
Yup, and some very large percentage of your power is now being dissipated
in the ground. Could be as bad as 80 or 90 percent, depending on how low
the actual radiation resistance of the L is. .
Worst antenna I ever had was a 40-10 trap vertical with the coax shield
going to the iron pipe driven into the ground as the support for the
vertical. SWR was PERFECT, all over the band. Performance was AWFUL. That
is spelled A W F U L.
Same antenna was also one of the best.
The very same antenna, mounted to a roof sewer vent pipe, with three 1/4
wave radials for each band, all above the flat barely sloped copper roofs
of Washington DC row houses, worked gang busters all over the world with
579's from a 35 watts out from an 807 transmitter. India, Antarctica,
Africa, Japan, all 48 states on 40 meters.
All reduced to barely heard in DC from suburban Va by an iron pipe ground
at green grass level. It might as well have been a wet noodle.
SWR does NOT predict performance. It just tells you when your transmitter
output circuitry will be happy. Just like transmitting into a dummy load.
73, y'all
Guy K2AV
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