What length and configuration have people used with their AH-4 and why? How many counterpoise radials, does using different length help? Anyone using more than one wire hooked up at a time? I live in the middle of a forest, and have a fairly large foot print available; with the hardship of being blocked in by trees that I do not have the ability to climb.
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Good morning, Kevin....
I've been using an AH4 for about 10 years on multiple bands (80-10) with pretty good success. Whenever I toy with the idea of putting up something different (e.g., dipole) I usually decide the long wire works pretty well and its just not worth the extra effort. As far as the AH4, after using homemade tuners for years, I believe it is a miracle tuner (LoL), especially when hooked up to an ICOM radio.
Now, to answer your question....
in the AH4 instructions, there is a section that talks about what lengths not to use (e.g., 1/2 wavelength) for a given frequency range. It includes a formula to use. Using the formula gets kind of tedious when trying to find good/bad lengths for multi band operation.
Some recommended lengths for 80-10 coverage include: ~72', ~106', ~136', ~172', etc....
I'm using 106', that starts about 10' off the ground, where my tuner is mounted, and then runs to a tree about 40' high. The last 15' or 20' runs horizontally through the trees to the down-rope.
From everything I've ever read about random wires.... LONGER IS ALWAYS BETTER and HIGHER IS ALWAYS BETTER! I have found (un-scientifically) that even a 15' higher wire seems to show an improvement in operation.
I've used bow and arrow, slingshots, and arborist's throw bags to get lines over the trees. A bow with an arrow tipped with 1 or 2 oz. of lead is the best. Can easily get a fishing line over a 120' tree. Odds are good someone in a local Ham club probably has the bow and arrow setup you need and will be happy to come over and help raise your lines.
Counterpoise - I don't exactly have a technically correct counterpoise. Most people use that term in a slightly incorrect manner.
What I do have is... my radios are directly next to an exterior wall. Immediately outside the wall I have an 8' ground rod with several #10 ground wires running inside to the equipment. From that first ground rod I have a ~60' run of #14 wire to a second 8' ground rod directly under the tuner. From that ground rod I run a ground wire up 10' to the tuner mounted on the side of the house. I have very damp sandy soil, and that may help my situation. A GOOD GROUND IS ESSENTIAL.
At one time I "tested" more "counterpoise" / radial wires running out from the ground point under the tuner. I added about a dozen, of 1/4 wave lengths for 40 & 20 meters. I don't believe it made much difference. The literature is a bit mixed on radials for random wire antennas with remote tuners, such as the AH4.
I have about an 85' run of control cable to my AH4 tuner and she works great.... Note: some have reported problems with any AH4 control cable length over 30'.
I have about 90' of RG-8U coax from my radio to the AH4 tuner. About 10' before the tuner I made about eight, 10" loops with the coax. There are many papers on the internet about why this kind of "balun" helps with HF and UHF coax fed antennas. Probably not needed with the AH4, but I've just always done it.
I have absolutely zero RF in the shack (100 watts PEP) and my SWR reflected power needle barely moves on all bands (160-6). The tuner takes about 1 second to tune as I change bands (hitting tune button on IC-706 and IC-7300). Once on a band, I never need to re-tune as I move up and down within that band, as the SWR reflected power stays very, very low.
I usually have no trouble working anyone I can hear.... and I have about a 65-75% success rate in big DX pileups on 20 meters.
I do believe long wires tend to capture noise a bit more than other antenna options. But I've never done a side-by-side test. Smart use of the RF gain on your receiver can easily negate any but the most horrendous noise issues. At my location (typical neighborhood with above ground power lines and houses on 1/4 to 1/2 acre lots), about 10% of the time the noise makes the bands unusable, 50% of the time I have moderate but workable noise, 20% of the time low noise, and 20% I have no discernible noise.
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I see no need (nor benefit) for multiple radiating wires from the tuner (especially if you have a technically correct length)... so have never tried it. Maybe others could weigh in on this topic.