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One man's opinion:
Get it as high as you can, use balanced line & the Matchbox. Coax has much more loss @ SWR 1:1 than balanced line. And you will have high SWR (on the feedline) on some bands. The plastic "window" 450 ohm ladder line is OK but acts funny when wet (SWR swings). All that plastic insulation is the culprit. Moisture on the plastic causes oscillations that wreak havoc on SWR. Best to make-up your own balanced line with as few spacers between the wires as possible. To disable the Matchbox relay, use a small bit of matchbook cover or old credit card between the relay contacts. That's what I did with mine & it's worked great for years. Very easy to revert back to the relay if you ever go to separate transmitter/receiver. I stay away from baluns when I intend multi-band use. They don't act the same at all frequencies. The Matchbox has no balun, the transmitter output is coupled to the transmission line via a link. Also, you can extend the range of the Matchbox (to cover 160). See a "how to" article in Electic Radio Magazine -March, 2001 issue# 142, page 10. Back issues are available for $3.75 he http://www.ermag.com/. 1. Is it worth the extra trouble to get ladder line and feed into the shack (house) (as opposed to coax)? I will have pulleys so I could try one and then the other. 2. What length should I cut it for? I am new, don't particular know what frequency I might be on. I had heard that the 160m loop (approx. 540' or so) could be good as a multi-band. What exact length should I aim for, or is it even critical? 1005/? 3. If I use ladder line, I would have to use a balun in the shack to convert to coax a short run to go to my Kenwood Tuner (which has 160m), on other bands I would use a small Johnson Matchbox which lacks 160m and eliminate this balun. I am envisioning some kind of old- fashioned DPDT knife switch, I guess. 4. Actually, as a newbie, I have a nothing but more questions, like how best to override the built in relay in the Johnson Matchbox etc. I am gradually figuring this stuff out and hope to find some locals also. |
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