Antennas On The Switch
- Palomar 95 (P95) - August -
September 2021: Tested remaining configurations of
antenna length, UNUN mounting height and
counterpoise use, configuration and length.
Settled on a wire 95.375 ft in length with the
UNUN at the top of the 30 foot flag pole,
and no counterpoise. Modeled this
configuration in 4NEC2 and compared it's predicted
performance to observed performance in PSK
Reporter while making hundreds of FT8 QSO's.
For my location with it's restrictions this
antenna length is ideal. In a less
restricted location I think I would investigate
the 200-300 foot antenna length. The MFJ
993b Antenna Tuner has made this configuration
really shine!
ZEP
Antenna Configurations
The Palomar Bullet 9:1 UNUN
connects the 50 ohm coax to a psudo-random length of
antenna wire. I say psudo-random because there
are specific requirements for the length that this
wire should not, and can not be. That would be
any lenght that is resonant on any band the antenna
will be used on. Picking a practical wire
length is non-trivial to operate on
80-40-30-20-17-15-12-10 Meters. In my case
where I am severely constrained, I believe I can get
away with about a 90' horizontal run combined with
the 30' height of the tall flag pole. An 95'
foot wire probably is the longest I can expect to
use at this location. 136', 140.5', 117.5' and
anything over 295' are options, but too long
(maybe).
NOTE: Fall of 2021 - After testing many lengths and
UNUN mounting heights, I have settled on a 95.375
foot wire length with the UNUN at 30 feet AGL.
This will be know as Config 12 and is likely the
final configuration of this HWEF antenna. My
QSL Notes will from October 2021 refer to this
antenna as P95.
The Bullet is rated at 200W FT8
The Bullet UNUN at 30' AGL, no
counterpoise, no guys.
Later I added a guy from the hoisting eye to the
fence in the opposite direction from the antenna
about 30' away. I plan to add another guy to a
flying anchor off the shack's front left corner
(near the 2M antenna) to relieve some of the stress
on the pole.
This is what it looked like at 55 feet.
Apparently I don't have a photo of the full length
95.375 ft antenna yet.
I'll swap out this photo and caption when I do.
Following are notes from each configuration I
tested.
The elements that were modified are the height of the
UNUN, the presence of a counterpoise, and mostly the
length of the antenna wire.
