A while back I purchased one of AD8HK’s end-fed random wire (EFRW) antennas. I tried it for the first time during my ill-fated Flight of the Bumblebees (FOBB) outing. With everything that went wrong that day, the AD8HK antenna certainly deserved a better evaluation—at least one where I wasn’t in a panic over problems with my newly acquired Elecraft KH1.
The AD8HK EFRW is a really slick little antenna. It consists of a 15-foot radiator and a 7.5-foot counterpoise wire. It has a neat 3-D printed winder for the wires that also incorporates a 4:1 unun and BNC connector. It’s compact and well-built. AD8HK Antenna Systems sells this antenna (and other offerings) through eBay.
During my infamous FOBB outing, I fed the antenna with 6 feet of RG-316 coax. It loaded up on 30M through 15M, but neither my KH1 nor my Elecraft T1 tuner could find a match on 40M. I’m not sure what the issue was, but I didn’t have much time to look into it.
Sometime later, tried the same length wires with one of my homebrew 4:1 ununs. That time I used 20 feet of RG-316, and it loaded up fine on all bands.
This morning I took the AD8HK EFRW over to Valley Forge National Historical Park (US-0761, KFF-0761) for an activation. I supported the antenna with a 20-foot pole and my homebrew ground mount. I fed the antenna with 20 feet of RG-316, and this time my T1 ATU easily found a match on 40M. It also loaded up fine on 30M through 17M.
A 15-foot radiator isn’t going to be a barn burner on 40M; however, this little antenna certainly held its own today. I easily logged 13 contacts on 40M before moving on to try other bands. When I wrapped up after a little over an hour, I had twenty contacts in the log, with four park-to-park contacts. I made contacts on all four bands covered by my Penntek TR-35 (40M-17M), and I was pleased to work W6LEN out in California on 20M.
After today, the AD8HK EFRW has definitely earned a spot in the KH1 kit I’m putting together. It’s easy to deploy and has a relatively small footprint.
Speaking of my KH1… I heard from Elecraft a few days ago. They replaced the FET in the final amplifier, and now the rig is on its way home. I can’t wait to get it back on the air.
72, Craig WB3GCK
WB3GCK QRP Amateur Radio 
Coax Is funny stuff. At 1/2 wave length the impedance seen at one end is matched at the other. At 1/4 wavelength the low impedance at one end is seen as crazy high at the other and a high impedance is seen as low at the feed. At odd lengths the ratios are all over. I have a 17 foot pole with a 4/1 balun at the base beside the house on a 10 foot pole in dirt as a counter poise. I dont know the length of rg8 to the base but the odd length of coax makes usable as is with a swr at 2 or less at 40 30 20 15 and 12 meters. It is usable at all from 40 to 6 meters with a small tuner. Having a Nanoanalyzer has opened up all kinds of neat experiments and opportunities.
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