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Author Topic: Antenna tuner won't tune  (Read 1815 times)
W5DXP
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« Reply #30 on: February 16, 2012, 03:58:42 PM »

When losses are low, that reactance may be
close to -j25 ohms (and we can make it exactly so if necessary for this example.) 

"Close to -j25 ohms" vs "making it exactly so" may be the difference between tuning an antenna system for lowest SWR and tuning the same system for maximum field strength.
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73, Cecil, www.w5dxp.com
Random length "tuned feeders" usually de-tune an antenna system!
KJ6TSX
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« Reply #31 on: February 18, 2012, 07:22:46 PM »

Thanks Guys for all the help, I am going to put up a folded dipole tomorrow morning, Wife wouldn't let me on the roof after dark<grin>
I have learned a whole lot since we started this thread. When I hook up my new antenna is it permissible to run ladder line through a metal vent on the side of the house that goes into my shack? and what precautions should I take?
Thanks Again
George
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W5DXP
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« Reply #32 on: February 19, 2012, 07:34:28 AM »

... is it permissible to run ladder line through a metal vent ...

The rule of thumb is: Keep the ladder-line a few inches away from any metal. On ladder-line with a SWR not equal to 1:1, there are current maximum points and voltage maximum points. The voltage maximum points are what we have to worry about arcing when there is metal around. If you don't know where the voltage maximum points are located then IMO it is not worth the risk to violate that rule of thumb.
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73, Cecil, www.w5dxp.com
Random length "tuned feeders" usually de-tune an antenna system!
AD6KA
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« Reply #33 on: February 20, 2012, 01:34:26 PM »

Quote
Wife wouldn't let me on the roof after dark<grin>
She's a keeper, that's a great rule.

There's a Robert Palmer song that's been recorded
by everybody fom Harry Belefonte to the Grateful Dead:

"Man Smart, Woman Smarter"  Grin

Ken,  AD6KA
« Last Edit: February 20, 2012, 01:40:14 PM by AD6KA » Logged
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