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#1
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Dave wrote:
I do appreciate all of the feedback, and the patience with my ignorance. Have you considered a screwdriver antenna? Many hams try a whip with an autotuner, are dissatisfied, and wind up with a screwdriver antenna for a 12 dB improvement, at least on 3.8 MHz. -- 73, Cecil http://www.w5dxp.com |
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#2
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Cecil Moore wrote:
Dave wrote: I do appreciate all of the feedback, and the patience with my ignorance. Have you considered a screwdriver antenna? Many hams try a whip with an autotuner, are dissatisfied, and wind up with a screwdriver antenna for a 12 dB improvement, at least on 3.8 MHz. ----------- (Spoken in Columbo's voice and mannerisms)"Uh, podden me, Cec, butta, 12db improvement compared to what?" A 108" whip tuned with an electronic autotuner at the base, on the trailer hitch attached to an average car should be just as (was gonna use the words efficient and effective - but thought better of it) as a short little whip mounted in PVC pipe at the same location, but using a mechanical tuner (screwdriver) instead of an electronic autotuner such as an AH-4. Yes, I have considered a screwdriver antenna, just don't know where to put it on my minivan(s). As you can tell, I'm coming in late on this one. Thanks for your patience. Ed, NM2K |
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#3
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On Mon, 12 Nov 2007 10:51:58 -0500, Ed Cregger
wrote: A 108" whip tuned with an electronic autotuner at the base, on the trailer hitch attached to an average car should be just as (was gonna use the words efficient and effective - but thought better of it) as a short little whip mounted in PVC pipe at the same location, but using a mechanical tuner (screwdriver) instead of an electronic autotuner such as an AH-4. Hi Ed, This is a bit garbled, but the sense is there. You are comparing a bad installation to a bad installation - yes one will be as efficient/effective as the other. The tuner at the base of the whip has invested resonance in the wrong place. A coil at the base of a whip also invests resonance in the wrong place. A coil higher in the whip invests resonance in the better places by degree. Ostensibly, the premium degree of coil placement is one half to two thirds the way up the whip. A screwdriver antenna attempts to make this resonance investment. If you will note, the coil section falls between a lower tube and an upper whip. There is a world of discussion as to why it is better that I will leave to others to fill in. 73's Richard Clark, KB7QHC |
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#4
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Ed Cregger wrote:
Cecil Moore wrote: Have you considered a screwdriver antenna? Many hams try a whip with an autotuner, are dissatisfied, and wind up with a screwdriver antenna for a 12 dB improvement, at least on 3.8 MHz. (Spoken in Columbo's voice and mannerisms)"Uh, podden me, Cec, butta, 12db improvement compared to what?" Compared to the aforementioned "whip with an autotuner". -- 73, Cecil http://www.w5dxp.com |
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#5
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"Cecil Moore" wrote in message et... Dave wrote: I do appreciate all of the feedback, and the patience with my ignorance. Have you considered a screwdriver antenna? Many hams try a whip with an autotuner, are dissatisfied, and wind up with a screwdriver antenna for a 12 dB improvement, at least on 3.8 MHz. -- 73, Cecil http://www.w5dxp.com Hey Cecil, Not sure what a screwdriver antenna is. Off to Google... Dave |
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