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PostPosted: Sat May 26, 2012 4:10 am 
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Joined: Sun Feb 28, 2010 2:12 pm
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I'm looking for some advice on an easy way to tune up a dipole.

I have a temporary 10m balcony dipole that I put up and take down as needed. When I originally cut it (on the balcony), it was resonant (or at least exhibited low SWR) at the low end of the band. Today I strung it up and it was resonant about 1 MHz higher. It's almost certainly detuning because of the cluttered balcony surroundings.

Rather than fiddle around with the dipole placement on the balcony, I want to just turn a knob and reduce the SWR.

The dipole is made of some medium-to-thin gauge stranded hookup wire with an RCA jack at the center. An RCA plug is plugged into the RCA jack at the dipole. The plug is soldered to a run of RG-58A/U coax that leads to the rig.

So is there an easy way to rig up a homebrew tuner that can reduce the SWR and not dissipate much of my precious QRP power? Any circuit recommendations for this case? If possible I'd like to tune at the rig, but if necessary I can put the tuner at the antenna.

Thanks in advance. 10m band conditions were tolerable this morning and I found a slow CQ that I was almost ready to respond to, but the antenna SWR was too high.


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PostPosted: Sat May 26, 2012 5:34 am 
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Joined: Sat Jun 06, 2009 6:58 pm
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Location: South Florida
There's no free lunch (have I said that before?) and no simple loss-less tuner.

Put alligator clips on a pair of wires. Set up the antenna, clip on the wires, then either bend back or trim the ends to tune.

73,

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PostPosted: Sat May 26, 2012 7:21 am 
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OK,thanks - that seems to work OK. I found that folding the excess length tightly back upon itself (in a 180-degree hairpin turn running right back along the length of the wire, instead of letting the excess hang loosely in a loop) seemed to give the most controllable and predictable results. A little cumbersome, but still manageable.


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