Ping:Frank (fcathell)
wrote:
I've used an LF Engineering L-400B active whip in the past and it would
pretty much out perform longwires less than about 1000 feet. IT's only
problem was intemod and overloading issues if MW stations were nearby.
Mine actually wore out due the intense UV from the S. CA and AZ sun. I
still have the electronic guts and should probably rework it for use
again. I do have the PAR Inc. high and low pass filters and they work
great on 50 ohm lines to eliminate intemod after a passive tuner.
Despite the local MW stations I don't have any problems at night and I
can force the situation most of the time during the day as long as
there are no amps in the signal chain.
Frank
Tucson
You might want to review the Burhans active antenna and think about
adding his
MW rejection filter. It works very well with most JFET active antennas.
There
was something odd about the Burhans LF match box. It has been too
darned
long, but I think one of the torroids he used, or his magnetic bias
scheme
caused some serious IMD. I have most of the RE Burhans stuff, but no
longer
have the one on the LF matcher. Maybe I can stop by the engineering
library Sat
and pull that one from microfilm.
Will is having great success with the Lankford active dipole, the AMRAD
is a
rather poor copy/clone of Dallas work and in the dipole mode, IP2 goes
up several
dBm. And you can rotate the thing to peak a signal or null a noise
source. Ron
Hardin uses several sets of McKay 100? single ended actives antennas
with multiple phasers to knock out multiple noise sources.
What receiver are you using? Must have a very tuff front end to survive
in the RF
hell you are discribing.
A friend once ran several hundred feet of scanged CATV
hardline down a drainage ditch and under a culvert to reach some nearby
woods
where he errected a ?3000' antenna pointed great circle at England. He
really
wanted MW transatlantic DX. He used a taped inductor and a ground rod
with
several hundred feet of radials and it was killer. At lower frequencies
coax loss
can often be low enough to allow such odd stealth setups.
Terry
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