[Pro2006] Scanantenna VS Icom AH-7000

Mike [email protected]
Sat, 16 Feb 2002 15:43:19 -0600


It was a nice weather day here in the midwest so I thought I would
put the Scanantenna up that many are asking about here in the groups
(and string a SW wire antenna). I just picked these frequencies because
they are all fixed repeaters and were most active at the time of my test.

I mounted the scanantenna with-in two feet vertically (scan antenna lower)
and 3 feet horizontally. This is about as close as I could get them but I think
the are relatively close as to avoid a 'sweet spot' that would affect the signal.
Fed with the same type low loss coax and of the same lengths. The Icom
is on top of the mast (discone) and the scanantenna is mounted so the mast
is behind the direction being received. This is only a rough test but I wanted
to share my findings for your information and discussion. I also had asked 
about the construction and possible issue of breakage and got some interesting
comments ( I will include them at the end of this e-mail). I hope this gives you
some ideas on the scannantenna and answers some of your questions.

Here is a break down of several signal strengths recorded over a short
period of time this afternoon. In summary it shows (from this very rough
test) that the scanantenna out performs the Icom in the low VHF band
while the Icom out performs the scanantenna in the UHF band. The 900
MHz band was a tie. One notable variation and I can't explain it but maybe
someone can give some thoughts. With the closest UHF signal the scan-
antenna did out perform the Icom (460.325) while in the rest of the tests
with stations a bit further away the Icom did better at UHF. These numbers
are average of several reception (the numbers did not vary much on each
antenna so the average is close to the mean. The lower the number the
better (stronger) the signal. These are not calibrated but reference numbers
only..

Freq.		Icom	Scanantenna

408.200		97	97
460.150		89	89
  42.460	  97	     92
155.655		87	87
460.225		89	90
460.275		94	97
460.175		97	98
460.325		86	83
858.9875	92	92

Lower is better (stronger)

Here are some other comments received on the 
scanantenna:

I'm kinda in the same geographic condition as you; surrounded by hills.
I have real good results using a mast mounted pre-amp, and RG6 coax.
Compared to my Diamond 510 (a 144/440 base antenna), I get almost as good results on
Vfh HI, and as good or better on Uhf. I can receive 800mhz out to around forty miles.

Another thing. Mount it on a PVC mast if you can. A steel mast does cause nulls.
I have mine mounted on a rotor.

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These antennas fall apart with little provocation.  I can almost guarantee
that it will to survive an Iowa summer with strong T-storms or a harsh
winter with a good blizzard or ice storm.  That being said, they do perform
quite well and snatching up a bunch of them at radio shack if they are cheap
might be a good idea.  As for where it breaks, mine always would break right
at the point where the elements attach to the boom.  I suppose a person
could attach a short piece of fiberglass rod at those two stress points to
stiffen the weak spots.

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They do tend to break. I went through 2 of them in 5 years.But the one i have now
i used outdoor epoxy glue were the element snaps up. Definetly helps hadnt had 
a problem since

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I have both. They are, as far as I can tell identical.
The Scantenna has been up for four years with no problem what soever.
Just make sure you put some silicone grease on the studs where the balun
attaches to the antenna.

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