Forwarded for W5DM:
To: <topband@contesting.com>
>Date: Wed, 08 Jan 1997 17:25:35 -0800
>From: Paul & Abbi Elliott <paab@wtaccess.com>
>Subject: 160m rcv ant
>X-Sender: paab@wtaccess.com (Unverified)
>To: btippett@CTC.Net
>
>
>To those who requested it, here is a summary of responses to my request for
>a good 160m receiving antenna for a 120x120 ft city lot.
>1. Several people pointed out that no small antenna, located in the noisy
>environment of a town, would be able to compete with a beverage in the quiet
>countryside.
>2. Two people suggested that phased loops would probably be my best bet.
>Another two suggested a "slinky" beverage as long as possible.
>3. One person had good luck with a 500+ feet in length loop around his
>yard--fed with a balun (like a quad on its side).. Said it worked nearly as
>good as a beverage, but not directional.
>4. One person in the northwest said that a K6STI loop (50 ft on a side)
>helps in the morning for the Pacific/Asia area but in the evening doesn't
>help at all!
>5. A couple of persons had good luck with EWEs; another said his EWEs on
>top of his little (1100 ft) mountain didn't work very well. (I have to
>comment on this. I am a "flat-land furriner", originally from South Texas.
>My conditioning makes it difficult for me to comphrend "little" applying to
>a 1100 ft mountain!). His 1/4 wave coax patterned from an article in
>LowBand Monitor magazine works OK.
>I will add a few observations about my experiences here. I have a friendly
>5kw AM broadcast on 1480 mhz about a quarter of a mile away. I do have
>trouble making some measurements on antennas. I have an honest 60 db band
>reject filter that I use on my receive antennas--my receiver does not show
>obvious signs of overload. My transmitting antenna is a semi-inverted L,
>longer than a quarter of a wavelength. By trial and error I made it just
>the right length so that when I tuned out the inductive reactance with a
>series capacitor it just matched the 50 ohm feed line--2/1 swr bandwidth is
>about 55 khz. I found that I got less noise reradiated, and less distortion
>in the receiving antenna patterns, if I grounded the capacitor-antenna
>junction during receive instead of (1) leaving the antenna connected
>normally or (2) opening the capacitor-antenna junction.
>All the receiving antennas (shielded loops,EWEs, 1/4 wavelength coax
>antenna) in general let me hear weak signals that are not heard on the
>inverted L. All the antennas appear to have normaly directivity on DX
>signals--they show little directivity on high angle signals. Usually the
>loops show better S/N ratio than the EWEs--the loops and the coax antenna
>certainly show more sensitivity than the EWEs. The EWEs are the only
>antennas that really need a preamp. My friend in the country hears very
>well on his EWEs. Even though I have no obvious localized source of noise,
>the noiser environment in town definitely makes life more difficult.
>I am going to mount a three-pronged attack. (1) I am going to get the
>pieces to build a two loop phased array. (2) While I am waiting for the
>pieces I will, if I can find the slinkys locally, try a slinky beverage.
>(3) Since I want my will to read, "Being of sound mind I spent it all", I am
>going to try to find some acreage in the country.
>My sincerest thanks and appreciation to all.
>
> 73 Paul Elliott, W5DM since 1968. a ham since 1937. If I make two
>more weeks, I will have been a ham for 60 years.
>
>
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