Author |
Message |
Kattracker
| Posted on Friday, September 26, 2003 - 9:14 pm: |
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I have seen an add-on device for mobile antennas and wondered if they are snake oil or if they really work. The device I am referring to is a radial attachment that would go under the mobile antenna that uses a 3/8 threaded mount. It looks like a ground plane kit. They come in different versions, from 3 radials to 5 radials. I have seen them advertised with the name tri-star etc. Has anyone used them or know anything about them? Thanks, Kattracker |
Kc0gxz
| Posted on Friday, September 26, 2003 - 10:24 pm: |
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Kattracker They're a joke. The radials aren't nearly long enough to work as a ground plane. And besides, how could those tiny add-on things even come close to being a ground plane when comparing them to the metal roof of your vehicle? Back in the 70s, there was another worthless CB "wonder item" called the Zing Ring. Those didn't sell very well either. People that DID waste their money on them soon found out why. Jeff, kc0gxz. |
Xlaxx
| Posted on Friday, September 26, 2003 - 10:41 pm: |
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Katt- Tech 833 commented on them under the antennas section. I used one for a while, got decent SWR's but no increase in signal/performance. Antenna Candy,...took it off,...don't waste your money or time. My 2 cents XLAXX |
Kattracker
| Posted on Saturday, September 27, 2003 - 9:47 am: |
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Basically what I thought. And if I am correct, if it were a base antenna, a ground plane kit would not be connected to the transmit/receive part of the coax/antenna anyway. Since this part directly connects with the antenna and you would transmit directly into these radials too, it seems it would do nothing more than change the ohm rating on the antenna. Maybe a help with high swr? Anyway I don't need it. My swr is near flat. But I am always looking for a way to eek a bit more performance out of the mobile. Kattracker |
Mr_Rf
| Posted on Saturday, September 27, 2003 - 12:48 pm: |
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Kat Since the radials are so short they appear to the trransmitter freq as high impedence and basically non-existant from an RF standpoint. Shouldn't change the SWR very much if any, and dedfinitely serves no purpose art the operating freq. However, at harmonics of the operating freq (2 times op. freq, 3 times op freq, etc.) they may become resonant and possibly cause increased interference to FM radio, aircraft, police, and TV receivers!!! Using these radials with amplifiers definitely aren't a good idea with regard to harmonic interference. My 2 cents. Mr_RF |
Bruce
| Posted on Saturday, September 27, 2003 - 2:28 pm: |
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Katt The same thing was marketed in the 70 's a set of grounding radiles only it was over a globe filled with water. Ok this is as good as sales pitches get ..... " You know how much better you sound over water well now you can mount your antenna over the water" like i said as good as it gets ..... save your money. |
Kattracker
| Posted on Saturday, September 27, 2003 - 6:13 pm: |
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Thanks for the replies. I thought they were worthless, ...but wanted to be sure. I didn't and won't buy one. Kattracker |
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