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Old February 12th 05, 05:09 AM
Howard
 
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On Fri, 11 Feb 2005 22:34:54 -0600, Cecil Moore
wrote:

Hal Rosser wrote:
or just use a piece of black nylon fishing leader


Also, the black UV resistant tie wraps should make
pretty good insulators.


How about using a wood dowel? Cut a suitable length, drill holes and
apply a few coats of varnish. Might work fine, though not as creative
as the poster who suggested buttons.
Howard
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Old February 12th 05, 06:46 AM
Graywolf
 
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"Roy Lewallen" wrote in message
...
I'd like to caution you against using plastic that's not intended for
outdoor use. Most types will deteriorate rapidly from the UV in sunlight,
and turn brittle and very weak in a short time. Even here in western
Oregon, most plastics become useless in a year or two, & in a place like
Denver (5000 feet high and lots of sun) you only get a few months at
most.

A better idea, in my opinion, would be to use fishing line as others
suggested, or make your own from a piece of ABS pipe or something
similar.

Roy Lewallen, W7EL

Cecil Moore wrote:
wrote:

I'm putting up a long wire antenna for a SW receiver. The area I live
in has severe restrictions, so I need to hide it, or at least have it
not be obvious. For the end insulators I was looking for small, about
1" long skinny plastic or ceramic insulators. I know they used to be
available, but I can't find them anywhere. Can anyone point to a
source for them? All I can find are 3" insulators with a 1" diameter.
These are much too obvious for me to use. Thanks.



Skinny insulators can be made from plastic coat hangers which come in
any number of different colors.


Roy et al.,

The polystyrene that plastic coat hangers are normally made from has a
moderately good ultraviolet resistance - much better than nylon
monofilament line.

But for a cheap, extremely effective, insulator which has excellent
ultraviolet resistance, cut the top off a PET soft-drink bottle (where the
screw threads are found). The dielectric properties are excellent and few
plastics fare better to ultraviolet and acid rain exposure than does
polyethylene terephthalate.

I have had a number of insulators up for years that were made from
fiberglass loaded PET tensile test bars. The only problem was dulling of
drill bits from the glass. A carbide tipped drill solved that problem.

73, Barry WA4VZQ



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Old February 12th 05, 12:41 PM
Pippa Reeves
 
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On Fri, 11 Feb 2005 15:55:45 +0000, melbjer wrote:


I'm putting up a long wire antenna for a SW receiver. The area I live
in has severe restrictions, so I need to hide it, or at least have it
not be obvious. For the end insulators I was looking for small, about
1" long skinny plastic or ceramic insulators. I know they used to be
available, but I can't find them anywhere. Can anyone point to a
source for them? All I can find are 3" insulators with a 1" diameter.
These are much too obvious for me to use. Thanks.

Jer


Try farm equipment suppliers..... You should be able to get suitable
items intended to be used as electric fence insulators.

Pip

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Old February 12th 05, 04:41 PM
Cecil Moore
 
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Pippa Reeves wrote:
Try farm equipment suppliers..... You should be able to get suitable
items intended to be used as electric fence insulators.


Most of those are ceramic and large but they make
excellent RF insulators.
--
73, Cecil http://www.qsl.net/w5dxp


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Old February 12th 05, 04:51 PM
Airy R.Bean
 
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A plastic cable tie, looped, is virtually invisible to
meet with the OP's requirements.

"Cecil Moore" wrote in message
...
Pippa Reeves wrote:
Try farm equipment suppliers..... You should be able to get suitable
items intended to be used as electric fence insulators.

Most of those are ceramic and large but they make
excellent RF insulators.





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Old February 18th 05, 07:26 PM
Jack Painter
 
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wrote

I'm putting up a long wire antenna for a SW receiver. The area I live
in has severe restrictions, so I need to hide it, or at least have it
not be obvious. For the end insulators I was looking for small, about
1" long skinny plastic or ceramic insulators. I know they used to be
available, but I can't find them anywhere. Can anyone point to a
source for them? All I can find are 3" insulators with a 1" diameter.
These are much too obvious for me to use. Thanks.

Jer


Jer,

No insulator is required. Either kevlar or cotton line (even when wet) have
about the same resistance as a wet or dry insulator, which is next to
nothing. Insulators or the lack thereof do not affect transmitting (1kw)
and they most certainly do not affect receiving. About the only thing the
special antenna-to-rope/line insulators do provide, is a form or strain
relief due to the wide-radius of turn around the insulator. This means when
the line holding the antenna breaks, it will probably break at your rope
knot, not at the soft-curve around the insulator. Big deal, huh. To conceal
a wire antenna, don't bother with insulators of any kind.

73,

Jack


  #17   Report Post  
Old February 18th 05, 08:24 PM
M. J. Powell
 
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In message 0krRd.48028$EG1.24274@lakeread04, Jack Painter
writes

wrote

I'm putting up a long wire antenna for a SW receiver. The area I live
in has severe restrictions, so I need to hide it, or at least have it
not be obvious. For the end insulators I was looking for small, about
1" long skinny plastic or ceramic insulators. I know they used to be
available, but I can't find them anywhere. Can anyone point to a
source for them? All I can find are 3" insulators with a 1" diameter.
These are much too obvious for me to use. Thanks.

Jer


Jer,

No insulator is required. Either kevlar or cotton line (even when wet) have
about the same resistance as a wet or dry insulator, which is next to
nothing. Insulators or the lack thereof do not affect transmitting (1kw)
and they most certainly do not affect receiving. About the only thing the
special antenna-to-rope/line insulators do provide, is a form or strain
relief due to the wide-radius of turn around the insulator. This means when
the line holding the antenna breaks, it will probably break at your rope
knot, not at the soft-curve around the insulator. Big deal, huh. To conceal
a wire antenna, don't bother with insulators of any kind.


Or use a large plastic button.

Mike
..J.Powell
  #18   Report Post  
Old February 19th 05, 12:02 AM
nick smith
 
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or a biro case drilled through at each end

Nick


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Old February 19th 05, 11:52 AM
M. J. Powell
 
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In message , nick smith
writes
or a biro case drilled through at each end


A button has the holes already drilled!

Mike
--
M.J.Powell
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