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Remote Baluns:

As we all know, many hams are forced to run compromise antennas, myself included. While this is much better than the alternative of not having ANY antenna, it also presents challenges to amateurs' technical abilities to come up with a design that's reasonably efficient while not being overly obnoxious to the neighbors. While at the same time providing you with a decent signal. I live in a so-called antenna restricted area (no towers) and after some squabbling with a homeowners association; I managed to put up a 40 ft push up mast for my limited antenna farm. While most amateurs in this situation can't even go this route, I was lucky in this regard. Now, faced with the challenge of being able to operate HF on 80-10 meters on one antenna is another matter... Since I could not push my luck by running cut to the band wires all over the yard, and risking further grief, I had to make due with an old stand by from the 30's, the 135 ft centerfed doublet. I strung this up in a typical inverted V configuration apexed from the top of the push up on a small homebrew PVC yardarm so as to get the feedpoint of the V away from the metal pipe. This antenna is fed with your garden-variety 450-ohm ladderline twin lead. This works pretty well on the lower bands as I ran the feedline directly into my shack and fed the line right off the internal tuners balun (4:1) All was well till one fine day wanting to work some DX on ten-meters, then I discovered that I had RF in my rig something terrible.

No matter what I tried, the RF was getting into my rigs audio circuitry and wreaking havoc. Discouraged, I had to find a solution to this. The answer is simple. Remote mount the 4:1 balun outside! (a current type is preferred for this) I purchased a balun and ran a short run of RG-8 coax outside to the balun and from there it feeds my 450-ohm line which runs straight up to my dipoles feedpoint. Now, there isn't any RF on any band at full power. While this is no news for veteran hams who have been around for awhile, I posted this article for new hams who are having the same problems with running open wire feed into the shack, or forced to run a single antenna for all bands. My problem was, I had no way to directly run the 450-ohm line into my shack without bends and close proximity to wiring and objects that most certainly caused the line to become unbalanced and radiate into my shack. This is lost power and highly undesirable for one seeking a decent signal!

Also, by remote mounting the balun, you get the best of both types of feedlines. You get the excellent shielding properties of coax inside, while keeping the multi-band capabilities of ladderline with very little loss. Sure, it's not perfect, but it sure beats RF in your rig, computer, phones etc. There are a couple of tricks for maintaining an easily tunable doublet using this system to keep in mind. For instance you run out of roller inductor on 80-meters all you need to do is add a short piece of ladderline to the existing run. Yes, I know, splices aren't exactly desired, but the loss of ladderline is so low, you wont even know it's there. Keep the line lengths on both conductors as close to identical as possible! If you do not, the line becomes unbalanced and you defeat the purpose of using it. If possible, try to run your ladderline at least a quarterwave long on the lowest band you operate on between your balun and feedpoint. This seems to help it tune up a lot easier and you will have lots of roller inductor left to play with on your tuner.

I have also read that many tuners internal baluns leave much to be desired. They aren't built heavy and many have very poor current balance on the higher bands. If you have an RF current meter available, just try and measure the current in your ladderlines conductors on higher bands and you may see as much as a 50% difference in current! (Several amateur antenna websites all agree on this.) Not very well balanced at all!

There are specific 4:1 baluns made for this type of application, (coax to ladderline) but I'm not going to endorse any products here; that's up to you to find one. If you read the product reviews section on this website, you can find some suggested baluns to try. While I admit that this isn't the worlds best set up, it does do a good job on the bands and I have no trouble working DX or anyone I can hear on any band, including the WARC bands. I believe that this system works well enough to suit most any ham who is stuck in the antenna restricted areas and can maybe sneak one up across a couple of trees for support. I also believe this outperforms the G5RV especially on 80-meters. Not that the G5RV is a bad antenna, but its short length on 80 degrades it somewhat on that band.

I would imagine a system like this could work well on full wave loops that are installed far from the shack. You could use this approach to limit feedline losses over long runs without running open wire into your shack and risking RF in your rig. Many of the audio experimenters would really benefit from this feed system to keep any stray RF out of sensitive audio equipment. A word of caution for Windom users -- a Windom is NOT a balanced antenna even though some use open wire for feeding them, the line actually acts as part of the antenna. The unbalanced condition would destroy a balun if used in this manner. Remember, a BALUN is for unbalanced to balanced feed, NOT unbalanced to unbalanced! I hope that any of this is helpful to hams both new and old.

73 DE KE4ZHN