Don't know if this went out or not, but discovered it in the Drafts dir.
My TH-5 at 100 feet was too high by all calculations, but that was the
only place I had for it and man did it play well on DX. If I could hear
'em, I could "usually" work them on one call. OTOH there were the
sloping dipoles anchored for 75 and 40, plus a single half sloper for
160 anchored under it which means it really wasn't 100' above ground.
OTOH I discovered I get good results with the FT5000MP running 200 watts
into an AV640 on a 25 foot mast on 40 and 20 compared to the center fed,
half wave, sloping dipoles (on 40) with the high ends around 90 feet..
BTW I ordered an ANAN-8000DLE. I like the numbers.
I figure with my network, I can run the rig from the house or shop
without the need for SO2R and all the associated switching along with
all the extra required coax connectors. I don't worry about loss in
connectors on HF. Even with UHF connectors. Even with the AIM it is
difficult to spot a UHF connector on 40, or 20.
If I sell all the excess equipment I can pretty much afford the OM
A4000, or save some money and get the little A2000+ which includes 6 meters.
I'd mount either amp in the basement, directly under the station in the den.
73, Roger (K8RI)
On 5/21/2017 Sunday 9:55 PM, Jim Brown wrote:
On Sun,5/21/2017 6:00 PM, Bill Turner wrote:
Antennas can be too high, believe it or not. Talking about DX, not
groundwave.
I've studied that extensively, and even wrote a tutorial applications
note on what I learned. It's pretty near impossible for most of us to
rig an antenna too high for bands below 30M -- a quarter-wave is low,
a half-wave is just starting to get good, and 3/4 wave is not too high
for anything but NVIS. My 40M dipoles at 120-140 ft play REALLY well.
That's about 1 wavelength high. My 30M dipoles are at 100 ft (also
about one wavelength). BTW -- contrary to widely held myth, 0.22
wavelength high is optimum for NVIS, and 0.33 wavelength is only 1 dB
down from optimum.
The tutorial app note is http://k9yc.com/AntennaPlanning.pdf
73, Jim K9YC
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