Hi Dallas,

I've been curious about your noise-reducing antennas some time, so this past
weekend I decided to build one as accurately as possible per your design. I
first got interested these antennas in the early 1990s during some e-mail
exchanges with Denzil Wraight in Germany.

I used the 3:1 turns ratio in the antenna transformer, and 18 ga. twinlead
speakerwire between it and the 1:1 transformer. The top of the 45 ft.
vertical is suspended to a branch in a tall tree, and the bottom end
fastened to a 5-ft. copper pipe in the ground. The antenna is located about
60 feet from the house, and my Wellbrook ALA 100 is 40 feet from the house.

I was quite surprised find not just worse noise from the vertical, but MUCH
worse noise. Signal levels seem good, but the noise is so bad the
readability suffers greatly, compared to the loop. For instance, this
morning past sunrise I was hearing JOAK in Tokyo on 594 kHz with an S-3
signal in Japanese, coming in nicely on the loop. However, the same
frequency on the vertical was just a strong BUZZZZZ of light-dimmer type
QRM. This was the most pronounced of the comparisons, but in most cases of
checking frequencies up through HF, the loop was the outright winner. I
tried to record 594 khz for comparisons, but I was using my modded R-75 and
didn't have the recording software configured properly since my last
DXpedition, and my SDR-1000 isn't fully hooked up at the moment. So, I
wasn't able to make a quick recording before the signal faded with
increasing daylight.

I did find a couple signals on the tropical bands where the vertical
provided a stronger signal with equal noise pickup (so therefore better S/N
than the loop).

However, my main interest right now is foreign MW signals. Do you have any
tips for improving this antenna's noise rejection on MW?

I can only think of two things that might impact the performance here. I
used the same type of binocular core ferrites that W8JI recommends, as I
have a lot of them. You used a traditional torroid form. Also, I don't know
how good the ground needs to be for this antenna to work well; the single
5-ft pipe may not be sufficient (soil here is reasonably good, though, clay
mixed with organic material...it's a forest floor).

Thanks in advance for any ideas!

Guy Atkins
Puyallup, WA
www.sdr-1000.blogspot.com



"R390A" wrote in message
ps.com...
Oops. It should be www.kongsfjord.no

R390A wrote:
To Whom It May Concern: Additions and revisions have been made to two
of my articles about vertical antennas and the ALA 100 on the
www.kongsfjord.com web site. The articles are (1) "Measurements Of
Some Antennas Signal To Man Made Noise Ratios In The Daytime MW And LW
Bands," and (2) "Some Of My Favorite Small Antennas For MW And LW." In
the first article an additional comparison of the ALA 100 was made with
an active whip antenna. The ALA 100 and active whip had about the same
signal to man made noise ratio. In the second article some information
was added about reducing noise in active whip antennas due to what are
believed to be ground loops in the DC feed.