The radiation pattern on the higher bands is complex with many lobes like the petals of a flower which means that a game of chance determines whether or not you are "beaming" in the right direction for a particular station. It's a compromise and dealing with ladder line requires more care than coax but if you can make it work, it's a great way to have fun on all HF bands with a single wire antenna. It's never going to substitute for a beam if you're really into busting pileups while chasing rare dx. I don't mean to imply that the ladder line doublet is the perfect antenna. Of course the impedence seen by the tuner depends on the length of the feedline. On 40m it becomes a center fed full wave dipole so the impedence in the center is quite high but despite that, the tuner seems to cope with it. I wonder now if I should have made it a little different to avoid extremes of impedence. I cut my doublet to 132 ft (40.2m) mostly because I followed the common instructions that say to make it a half wave on the lowest frequency. I would much prefer to have ladder line all the way to a tuner and not need to bother too much about measurements. People seem to spend a lot of time messing with the length of antenna or feedline trying to get an acceptable SWR on multiple bands. The common configuration for the G5RV is ladder or window line for a certain length and then coax to the shack. It can be a subject of heated debates on places like the qrz.com antenna forum. It's a similar antenna and I don't think there is anything "wrong" with the G5RV so long as people recognize its limitations when trying to use it without a tuner. I think it is sometimes overlooked by new hams who are more likely to turn to the G5RV for multiband use. My experience is that the center fed doublet with ladder line to a tuner is a great multiband antenna. Some thoughts on ladder line, doublets etc The batteries can last a couple of years. It uses latching relays so it draws very little power except when it tunes but it seldom needs to actually tune because it can return immediately to a previous setting in its memory for that frequency. It runs on an internal set of AA flashlight batteries. I can't easily use the manual tuner here because I don't have the ladder line coming into the shack like I did in Mont Vernon so I went back to the LDG and it's working well well. I used that successfully for several years and put the LDG away when it came back repaired. LDG happily repaired it under warranty but while it was away, I asked my dad in New Zealand to find and mail me my old MFJ-941D manual tuner. That worked well for a while until it overheated and burned a coil while operating on 20m CW. It worked for a few hours and then refused to tune. Then when I wanted to get on the air at the Mont Vernon QTH several years later, the SG-239 was pressed into service. When I was on the air briefly in 2003 I purchased a SGC SG-239 which worked okay but I didn't have a good antenna. Until recently I haven't had much luck with automatic tuners. I've had considerable success working DX on both phone and CW. It's working nicely on all bands 80 to 10m (well almost, see below). Coax then goes out the same window, down the side of the house and into the basement. ![]() ![]() My solution is to bring the feedline in through a window into the attic where I have a balun and automatic antenna tuner. I have a MFJ window feedthrough but that doesn't work with the small sliding windows in the basement. My "shack" is in the basement which presented a bit of a problem of how to get the ladder line in. ![]() It's a classic doublet which is a half wavelength long on 80 meters fed in the center with ladder line. I've put up the same multiband doublet I had at Mont Vernon. Of course the first ham project here has been to get an HF antenna up. We're back in the old QTH of Wilton, New Hampshire.
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