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#11
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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 |
#12
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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 |
#13
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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 |
#14
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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 ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 100,000 Newsgroups ---= East/West-Coast Server Farms - Total Privacy via Encryption =--- |
#15
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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. |
#16
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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
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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
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or a biro case drilled through at each end
Nick |
#19
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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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