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Old December 5th 03, 05:56 PM
'Doc
 
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Max,
An antenna as you described would make a good wireless
'dog fence' on 160 meters, but that's about it, I'm afraid.
Just slightly 'better' on 80 meters, and on 40 meters, just
very slightly 'better' than that. It will become 'almost-
an-antenna' on bands higher than 40 meters where it's length
is more than just a fraction of a wave length, but don't expect
much performance, NVIS or not. That's for transmitting. On
the other hand, it'll make a very quiet recieving antenna for
bands where it's length is more than a small fraction of a
wave length.
From what you say (no supports of any kind for an antenna)
I think you are going to be 'hurting' for an HF antenna, other
than a vertical of some kind. Is there any way you could
attach a wire doublet of some length to the eaves or peak of
your roof? Doesn't necessarily have to be of any particular
lengths or symetrical shape Longer is better), although that
would peobably help. Any height is better than no height,
as you'll be finding out...
'Doc
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Old December 5th 03, 07:13 PM
VE3TMT
 
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"'Doc" wrote in message ...
Is there any way you could
attach a wire doublet of some length to the eaves or peak of
your roof? Doesn't necessarily have to be of any particular
lengths or symetrical shape Longer is better), although that
would peobably help. Any height is better than no height,
as you'll be finding out...


Hello Doc,

I am on the ground floor of a two level apartment building. No roof to get
at and no eaves. My unit itself has 3 floors counting the basement where
the shack is. I was running a vertical, about 25' hung from under the
balcony above me, totally invisible, except being so close to the building
itself, the noise levels on 40 and 20 made those bands useless. Also being
vertically polarized, it was causing RFI on the computer upstairs, and
probably the neighbours as well. I have no way of running anything
horizontal above the ground as this would involve climbing and hard to do
that without the neighbours noticing. I have a feeling the property managers
will be doing some work on the balconies in the spring anyway, so the
antenna would surely be noticed then. I think I am going to go for the
ground laid antenna and hope for the best. My other alternative is a 8' CB
whip with a flag on the top, which has been up before without any problems.
This antenna is however too short to load on 40 with the tuner.

Thanks for all the input guys, I will scratch my head some more, maybe I
will think of some way to hang something from the balcony.


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Old December 5th 03, 08:06 PM
'Doc
 
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Max,
If nothing else presents it's self, you might try a
'CCD' (Controled Capacitance Distribution antenna). The
biggest draw backs are that they are a wave length long
and use silver mica capacitors that are not cheap. But
it can be laid on the ground and they do work. There's
a pretty good writeup in one of the ARRL's Antenna
Compendium books, not sure which one. It wouldn't be my
first choice in your situation, but it is an alternative.
'Doc
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Old December 5th 03, 08:50 PM
VE3TMT
 
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"'Doc" wrote in message ...
Max,
If nothing else presents it's self, you might try a
'CCD' (Controled Capacitance Distribution antenna). The
biggest draw backs are that they are a wave length long
and use silver mica capacitors that are not cheap. But
it can be laid on the ground and they do work. There's
a pretty good writeup in one of the ARRL's Antenna
Compendium books, not sure which one. It wouldn't be my
first choice in your situation, but it is an alternative.
'Doc


Thanks Doc, I'll look into it. At this stage in the game I am open to any
suggestions!!


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Old December 5th 03, 11:39 PM
 
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On Fri, 5 Dec 2003 14:13:37 -0500, "VE3TMT" wrote:

My other alternative is a 8' CB
whip with a flag on the top, which has been up before without any problems.
This antenna is however too short to load on 40 with the tuner.


Interesting. How about mounting the whip on a small bike (for
extra height) and attaching an orange pennant to the top? Looks just
like the things some parents have their kids use for visibility when
riding near cars. Should questions arise about the feedline -- uh,
it's for theft-proofing?



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Old December 6th 03, 11:27 PM
William F. Hagen
 
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How did you find out? That is exactly what I use as a stealth antenna. I have a
bicycle out in front of theapartment in the bike rack, with the very whip you
described with the triangle orange flag on the top to decieve the cops, and I
run coax from the house to the bike, running it up the kickstand, across the
frame to the 'flag' on the back. With it parked in the bike rack here at the
apartment complex with all the other kid's bikes, no-one seems to notice a
thing. I keep the power down on transmit just in case some kid just happens to
be getting his bike from the bike rack at the same time I am txing.
jkhh
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Old December 6th 03, 12:19 AM
KC1DI
 
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On Fri, 5 Dec 2003 14:13:37 -0500, "VE3TMT" wrote:


"'Doc" wrote in message ...
Is there any way you could
attach a wire doublet of some length to the eaves or peak of
your roof? Doesn't necessarily have to be of any particular
lengths or symetrical shape Longer is better), although that
would peobably help. Any height is better than no height,
as you'll be finding out...


Hello Doc,

I am on the ground floor of a two level apartment building. No roof to get
at and no eaves. My unit itself has 3 floors counting the basement where
the shack is. I was running a vertical, about 25' hung from under the
balcony above me, totally invisible, except being so close to the building
itself, the noise levels on 40 and 20 made those bands useless. Also being
vertically polarized, it was causing RFI on the computer upstairs, and
probably the neighbours as well. I have no way of running anything
horizontal above the ground as this would involve climbing and hard to do
that without the neighbours noticing. I have a feeling the property managers
will be doing some work on the balconies in the spring anyway, so the
antenna would surely be noticed then. I think I am going to go for the
ground laid antenna and hope for the best. My other alternative is a 8' CB
whip with a flag on the top, which has been up before without any problems.
This antenna is however too short to load on 40 with the tuner.

Thanks for all the input guys, I will scratch my head some more, maybe I
will think of some way to hang something from the balcony.


HI all

In your Circumstance I would opt for a small transmitting loop.. that
you could set out when on the air and bring in when not.. Though the
small loop is very Hi-Q and has to be retuned every few KHZ. it would
be a good compromise for you as they work really well when mounted
vertically close to the ground. they offer all radiation angles from
0 to 90 degrees and will give you plenty of qso's .. give it some
thought and I bet you can even find ways to hid one.. in the yard.

73 , Dave KC1DI

P.S. a google search for small transmitting loop will return numerous
pages to explore on the topic.



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