What follows are excerpts from an email reply to a customer that purchased a 240', end to end, 160M Doublet with 150' of feedline.. He was reading a lot of "expert" comments on the web about how much trouble it is to tune 600 ohm feed and was a bit concerned about what he may be in for.
Reading about open wire line on the internet is certainly going to make your head spin and ask yourself “oh man; what have I done?" I'd rather you worried about the future of our economy with the Gov't shut down.
Most of the "experts" have never used open wire line or, they are so anal retentive that they have to "model" everything to death and then tell everyone else that there's won't work unless they follow exactly what they did.
Most people that use an open wire fed antenna, with the 600 ohm feed, not the 450 stuff, follow good, practical antenna installation techniques, use a quality tuner and balun WITH THE CORRECT RATIO (which thankfully, you have), and you're on the air.
Sometimes, you may want to shorten the end to end length a bit and/or change feed length a little.
Most times, if you keep the feedline away from anything that can cause an imbalance, keep each leg off the ground symmetrically, allow the feedline to swing free (don't tie it to things), AND, use good grounding tactics in the shack, you won't have to do anything. It's really just a few percent of installs that have any work to do at all.
For instance, I always bring one of my doublets to Field Day, both winter and summer. We find a tree to toss a line into for the apex to use as an inverted V. I find a spot to setup my tent and table, pull the feedline over to my tuner, cut it, connect to the tuner and I'm on the air with all bands for the day. It really can be that easy. In fact, if I didn't place the feedline spacers every two feet so I could count them to determine the length, I would never know what it was. I am usually not concerned with the length unless, it ends up at 66’ or so and causes problems on 20M.
I helped a guy over the last few weeks that had your exact, same setup (tuner and balun) only he wanted to use the Balun Designs 1171T tuner balun. In many cases, that’s the right combo. He had all kinds of problems trying to get all band operation. I disagreed and said I really think he'd be better off with the 4114T. We worked on this for three weeks and tried everything BUT a different balun.
So, I purchased one and sent it to him to try. Guess what? It worked and solved his problem. He was running high power with a new, solid state, auto tune amp as well.
Balun Designs is the best in the business but sometimes, things just don't work the way we think they should. We just have to be open to trying something different.
If you have to change feed lengths, it's not a big deal. I just read on QRZ of a guy that changed lengths multiple times and soldered each connection, every time. That's kind of stupid. Just twist the wires together, go inside and try it. If not, untwist, take a little more off and repeat. When you find a length that works ALL bands AND full power, now you solder.
This is where an antenna analyzer can come in handy. When I had problems on my 160M version, not being able to tune the low end of 160, I used my MFJ-259 to determine that the SWR was above 25:1. My MFJ-998 couldn't go that high. So, I had to make changes to drop that within range, knowing it would solve my problem. I wasn't cutting and changing lengths blindly. I knew where things had to go. Of course, if I wasn't going to use 160, I would have stopped making changes anyway.
There's a photo on my site about how you tie a knot in the line, solder that area and tuck it inside a spacer and you're done.
Heck, for my 88' feed on my 160 doublet in Vermont, I never went back and soldered it. EVER! I left the wires twisted for about four years. There should be no stress on the feed or the antenna, to cause anything to pull apart.
I hope you can sleep after this email and have a laugh!
I have no clue who sent this to me as it was labeled anonymous sender. I just thought since it came out of nowhere, it would make a nice, quick post."I bought a 40 meter doublet from K5JYB a number of years ago. I'll never use another antenna unless I find room for the 80 [...]
Baluns for Multiband Antennas fed with Open Wire or Ladder linePosted by Bob, KZ5R on November 20, 2014 At least once a week we receive a request a for high ratio balun to manage the transition from high impedance open wire feedline to [...]
A bunch of us hams get together on Friday nights to work on various projects and when boredom sets in, we often search YouTube for some fun videos. This one never fails to bring lots of laughter. Enjoy!
This is a photo I took of my 10-160 meter doublet on the morning of May 9, 2017. At our elevation in the mountains, we tend to get snow when the valley's are left untouched.The auto tuner didn't seem to mind one bit and I was on 80M for part of the morning, chatting with [...]
Many of my customers call me after they've attempted to setup their complete True Ladder Line antenna system and report problems with the tuning. This can be pretty frustrating as well as easily solved, in most situations.Many times, the balun being utilized is just not up to the task demanded of it. I hear this [...]
I get that question quite often and it's pretty difficult for many hams to try to comprehend the use of a non-resonant antenna system. All we are conditioned to think about is 50 ohm cable, a matched, resonant antenna and attempting to tune for that perfect 1:1 SWR. Here's just a copy/paste response to an [...]
I am a member of BARS (Beaches Amateur Radio Society) here in Jacksonville Beach, Florida. My wife and I are here for the winter. The club holds their own "winter" field day and ours was on Saturday, February 4th. We operated at a shooting range and lodge for the Fraternal Order of Police. A wonderful [...]
Author R. Scott Rought, KA8SMA has an article in the December issue of QST.The title of the article is "IMPROVING QRP STATION EFFICIENCY", "The Wonders of Ladder Line. The only problem is, there's no ladder line pictured in the article!I see some of the old-fashioned twinlead as well as 450 ohm WINDOW LINE. I have [...]
How much tension should I tighten the flat top to? In other words, "should I really tighten up the ends as much as possible?" The answer is "NO"! I occasionally have a customer that will email or call and tell me that the antenna has failed and the wire has broken near the center feedpoint. This is not [...]