A while back, I built a J-Pole (aka “Copper Cactus”Smilie: ;) antenna for the 2-Meter band.  The intent was to put it up in the peak part of the attic, which would be the highest spot possible without getting it above the roof line.  Not thinking things through as usual, it ended up being too tall to fit there. I ended up just putting it down at the second-story floor level, in one of the unfinished storage areas.

I ordered a bunch of LMR-400 (aka “the good stuff”Smilie: ;) line to feed it from the office downstairs (directly below said storage area).  This weekend I got around to running the line and mounting the antenna in somewhat of a formal fashion.  Until now, I had it clamped in place, fed with a 50′ length of pre-made RG-58U (aka “the bad stuff”Smilie: ;).  Turns out, the line loss was so bad (about 2.8 db one-way I think) that the SWR always showed about 1:1 and there was no tuning to be had, presumably because the line was just losing it all by the time it got back to the radio.

Switching to the LMR-400 was a huge difference.  The loss with it should be about 0.8 db.  Immediately upon testing at 146.0 MHz, the SWR was about 2.3:1 with 25 watts.  After about 30 trips upstairs and back, I got the SWR down to 1.2:1 at 148 MHz and about 1.3:1 at 144 MHz.  Not too bad for my first J-Pole!

After I get the radio put back in Taylor’s car, I hope to be able to really test this on 2-Meter simplex.  Previously, I was able to get a good signal out to her with 2.5 or 5 watts as soon as I could hear her (when she was using 50 watts and a small antenna).  Hopefully, this will extend my receive range, making her 50 watts a little more effective.

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