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Jim wrote:
And, one other idea !! (found on the bay of "e"), and available elsewhere- a mount for 2 of these (or the hustler, and an Iron Horse, ect) "1/4" wave antenna -- first antenna goes to center of coax, second goes to shield!! makes a dipole, about 15 foot long, and can be mounted to mast (conductive, or plastic, same diff! tho the impedence will be quite low (because of these loaded whips), and the effeciency will be also not the best, at least would be an effective counterpoise!! and, to boot, parts available to build adaptor at rip-off shack!! got whole thing off epay for about 50 bux, + shipping!! Jim NN7K What do you consider to be the purpose(s) of a counterpoise? -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Jim wrote:
BTW that is Both Antennas, and the adaptor- not too expensive- cheaper when need only one ant, and the adaptor. It works well enough above 14 MHz, but such an antenna for 75m is a real dog. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Ron wrote:
I have a Hustler amateur mobile antenna model RM-80 for 80 Meter 25-30 KHz. Although it was designed as a mobile I want to use it as a portable, can anybody tell me the length of the counterpoise needed for this model? or can I just use an earth wire Use another RM-80 as the counterpoise. Hmmmmm, a 2% efficient antenna with a 2% efficient counterpoise. :-) -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Hey Cecil, 4% is better than 2%, and a 'hunerd'% increase
in efficiency! (I agree with you anyway...) 'Doc |
'Doc wrote:
Hey Cecil, 4% is better than 2%, and a 'hunerd'% increase in efficiency! (I agree with you anyway...) A 2% efficient radiator and a 2% efficient counterpoise doesn't add up to 4% total efficiency. :-) Anyone who wants a portable rotatable dipole on 75m can do much, much better than two Hustlers. Two SD-20 poles with high-Q loading coils in the middle of each comes to mind. And that's not much more trouble than two Hustlers. The SD-20 approach is available at http://www.wr6w6.com -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Counterpoise is required for most antennas to operate "effeciently" (have
you ever tried to load a 1/4 wave whip (without one)? Makes great dummy load! Dont radiate worth a darn! Needs the full "1/2 wave" to radiate effectively say that as can be done with loading coils, ect to shorten the effective length, or a ground media for the 1/4 part to work against (tho, at vhf there are SOME 1/2 wave , base coupled antennas that need no counter poise-- but then talking 75 meters- 125 foot tower to do that!! Cecil wrote: Jim wrote: And, one other idea !! (found on the bay of "e"), and available elsewhere- a mount for 2 of these (or the hustler, and an Iron Horse, ect) "1/4" wave antenna -- first antenna goes to center of coax, second goes to shield!! makes a dipole, about 15 foot long, and can be mounted to mast (conductive, or plastic, same diff! tho the impedence will be quite low (because of these loaded whips), and the effeciency will be also not the best, at least would be an effective counterpoise!! and, to boot, parts available to build adaptor at rip-off shack!! got whole thing off epay for about 50 bux, + shipping!! Jim NN7K What do you consider to be the purpose(s) of a counterpoise? -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Oh, and BTW, never stated it would be the "Best" antenna, But, surely would
be easier to pack, and set up, then packing a roll of wire , aprox. 67 feet long, and haveing to retrieve it later!! and, would be willing to bet, even as lousey is this is, would beat that one manufactured by a certain outfit that is about 3 foot high, and LOADS up your coax (ISO-T) to avoid lawsuits, like they involved 73 in years ago . Ron-er Jim NN7K Counterpoise is required for most antennas to operate "effeciently" (have you ever tried to load a 1/4 wave whip (without one)? Makes great dummy load! Dont radiate worth a darn! Needs the full "1/2 wave" to radiate effectively say that as can be done with loading coils, ect to shorten the effective length, or a ground media for the 1/4 part to work against (tho, at vhf there are SOME 1/2 wave , base coupled antennas that need no counter poise-- but then talking 75 meters- 125 foot tower to do that!! Cecil wrote: Jim wrote: And, one other idea !! (found on the bay of "e"), and available elsewhere- a mount for 2 of these (or the hustler, and an Iron Horse, ect) "1/4" wave antenna -- first antenna goes to center of coax, second goes to shield!! makes a dipole, about 15 foot long, and can be mounted to mast (conductive, or plastic, same diff! tho the impedence will be quite low (because of these loaded whips), and the effeciency will be also not the best, at least would be an effective counterpoise!! and, to boot, parts available to build adaptor at rip-off shack!! got whole thing off epay for about 50 bux, + shipping!! Jim NN7K What do you consider to be the purpose(s) of a counterpoise? -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
On Sat, 08 May 2004 09:12:50 -0500, Cecil Moore
wrote: Ron wrote: I have a Hustler amateur mobile antenna model RM-80 for 80 Meter 25-30 KHz. Although it was designed as a mobile I want to use it as a portable, can anybody tell me the length of the counterpoise needed for this model? or can I just use an earth wire Use another RM-80 as the counterpoise. Hmmmmm, a 2% efficient antenna with a 2% efficient counterpoise. :-) Hmmmm, I wonder what 2% efficient means. 2% radiated power with 98% reflected back into the radio? Ability to contact only 2% of the stations that you can receive? What? Ron, W1WBV |
On Sat, 08 May 2004 13:51:15 -0500, Cecil Moore
wrote: 'Doc wrote: Hey Cecil, 4% is better than 2%, and a 'hunerd'% increase in efficiency! (I agree with you anyway...) A 2% efficient radiator and a 2% efficient counterpoise doesn't add up to 4% total efficiency. :-) Anyone who wants a portable rotatable dipole on 75m can do much, much better than two Hustlers. Two SD-20 poles with high-Q loading coils in the middle of each comes to mind. And that's not much more trouble than two Hustlers. The SD-20 approach is available at http://www.wr6w6.com The question was the length of a counterpoise, not a rotatable dipole. I figured another Hustler sure beats running radials out in a portable situation. If someone was to ask you how to make their Chevy run better would you tell him to get a Ford? ;-) Ron |
Ron wrote:
wrote: Hmmmmm, a 2% efficient antenna with a 2% efficient counterpoise. :-) Hmmmm, I wonder what 2% efficient means. 2% radiated power with 98% reflected back into the radio? Ability to contact only 2% of the stations that you can receive? What? It's a ballpark estimate and means for every 100 watts going into the antenna, two watts are radiated. If the feedpoint impedance is 50 ohms, 98 watts are dissipated as heat in the antenna, primarily in the coil(s). (Try transmitting 100w into a 75m hamstick for one minute and then grabbing the coil.) -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
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