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Yeah, I noticed the same thing with the motorola triton, another antique....
maybe the newer ones aren't so quirky? W "Dave Platt" wrote in message ... Well, with the remote autotuner you will have less RF in the shack... But even then I would hang ground radials off the tuner case to keep it at lower voltage potentials... Definitely! One of the characteristics of the SGC autotuners is that they seem to *require* a really good RF ground. Their tuning circuitry "wants" to work into a ground connection which has a lower impedance than the wire. SGC's manual makes this point repeatedly, and identifies "grounding problems" (poor bonding, high inductance, etc.) as the commonest cause of "Hey, this thing won't tune" problems with their autotuners. My own experience with a used, older-model SGC 230 (so old it's in a non-waterproof metal case) seems to back this up. When used with a relatively simple ground, the tuner has serious problems in achieving a match, and frequently won't ever find one. I tend to think that these arbitrary-wire tuners work best in their original environment - bolted to a really big, solid chunk of metal such as a ship body or a tank. Another "gotcha" - the tuner I have, at least, can become seriously "confused" if you try to use it with a radio that has aggressive "high SWR power reduction" circuitry to protect the finals. In such a radio (my Kenwood TS-2000 is one), the output power jumps around a lot as the autotuner tries different L-network match settings, and the tuner firmware seems to misinterpret these transmitter power changes and never actually finds a low-SWR match. The same tuner, and the same wire and grounding setup, will often match within a few seconds when power is applied from another transmitter which doesn't alter its output power so abruptly (e.g. a Ten-Tec Scout 555). I've given up trying to use my old SGC-230 - it's so quirky that I just can't depend on it to work acceptably in my environment, with my radio. Other vendors' autotuners may be less of a problem in this respect. Since you are willing to spring for an SGC, etc. given your description of your site I would think about an off center fed wire antenna... Run your longwire through the trees... Roughly an 1/8 wave lowest band back from one end of the antenna drop a vertical wire to the ground and use the tuner to feed the end of the drop wire... A ground stake and some radials and you are likely to be in business... I'd recommend following SGC's recommendations... which probably add up to "lots of heavy radials". -- Dave Platt AE6EO Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
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