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Antenna phasing makes a difference
After waiting for the second Alpha Delta DX-SWL Sloper for two weeks and one finally arrived.
The first sloper is installed off the tower at 50' and I hung the second sloper at 40' up the tower at 40 degrees from each other.
I'm sure most of you know what a Quantum Phaser from Radio Plus Electronics is but for those who don't... it simply combines signals from two different antennas in such a way that a null or peak of a target station is obtained. In other words, you null one station out to hear another station on the same frequency.
The Quantum Phaser is a standard broadcast device only, so for those of you who enjoy listening to your favorite talk radio, such as myself, or AM music or sports you might want to play with one.
Over the winter months I'm going to try and log as many frequencies as possible to see what lurks in the crowded channels and to see what modifications I need to do with the antennas, such as spacing.
After a quick scan on the higher AM frequencies I was able to listen to two different stations on the same frequency on a few frequencies. Without the phaser I couldn't hear anything but garble, so it seems to work as advertised. So far, I'm pleased with it.
Here's a link to their web site for anyone who hasn't read about it:
Harry, W5HC,, November 2002

I am one of those that know what the Quantum Phaser is. Of the three commercially available Phasers (Quantum, ANC-4, MFJ) this one is by far the easiest to operate and to to get a null. I have used all three.
Note - the MFJ needs to be modified to work on MW/AM.
I have several products from Radio Plus. They are all top notch. Gerry Thomas is a genius and great to work with.
Russ, K3Pi,, November 2002
Two phased antennas produce a "V'' null that you can sweep from one endfire to the other. It's actually a cone, but the trace on the ground is a V, opening up to a plane at exact broadside.
[Even that differs from a loop, which always has point (not plane) nulls in opposite directions.]
A difficult station to null is best placed at endfire, so there are two nulls in its vicinity.
Increased separation gives you an advantage up to a quarter wavelength.
Any separation (no matter how close) gives you nulls but costs you gain in directions not nulled. That cost in gain becomes zero at a quarter wavelength separation.
At zero separation, you null all directions at once, the ultimate cost in gain. But you don't need full gain on MW, where the point is eliminating competing signals, not so much pulling up weak isolated ones.
If the antennas themselves have patterns, they multiply the phased array pattern.
A loop as one antenna lets you actually use zero separation, giving you in effect a free quarter wave through responding to the magnetic field rather than the electric field. As with two similar antennas, you get a V pattern which you can sweep from one endfire to the other. Endfire in the case of a co-located loop and whip is in the plane of the loop, that is, at the maximum of the loop alone.
The loop has to be broadband to successfully null a station across its entire bandwidth, otherwise there's no single gain that exactly cancels the whole station. So a tuned loop won't work as well as an untuned one.
The loop plus whip is a great option though if you have zero real estate to work with.
Phasing two loops is much harder than phasing two whips because except at the native maximum of the loops, the signals they give have much less stable phase and gain (at the native nulls, broadside to the loops, the signals are completely unstable and no setting of the phasing unit will work very long).
So to null a station with two loops, paradoxically you should aim the loops to maximize that station, unless it's daytime and the signals are very stable. Two loops have to be separated like two whips do, up to a quarter wave, with the same benefits.
Electrically combining two close loops or whips essentially gives you a single loop or whip. Only the combination of one loop and one whip works usefully at zero separation.
Ron Hardin,, November 2002
One of my reasons for buying the Phaser was to see if I could listen to a couple of local stations on 1180 kHz and 1280 kHz at night.
WGAB, 1180 kHz, reduces it's power from 670 watts in the daytime to 1 watt at night. I wonder what the coverage of 1 watt is? 1180kHz on the Drake R8B at night is covered by stations and none is dominate except a Spanish station from God only knows where.
With the Phaser I'm able to null the Spanish station out and WHAM in Rochester, NY comes in perfectly clear. I never heard it before tonight. Ummm, Michael Savage is on now. I like him because he doesn't like anyone.
On 1280 kHz WGBF is a 5000 watt daytime station and a 1000 watt night time station. I'm about, ohh, maybe 20 miles as the crow flies from both WGAB and WGBF and there's a pretty good hill between us. WGBF at night time is mixed with other stations and never Q5 copy until tonight. Another notch for the Quantum Phaser.
The phaser also did clean up 1510 kHz, WLAC in Nashville, TN. Although, if I want to listen to Art Bell, I usually tune in 1100 kHz, WTAM in Cleveland, OH and never bother with WLAC.
This phaser is an interesting little gadget!
Harry, W5HC,, November 2002
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