Tuesday02 June 2026 Whatever MODE is your preference these days for Dx'ing on 160m, it is still extremely important to hear well. A couple of weeks ago I gave a speech at the Topband DInner in DAYTON - and one of the things I talked about was this 160m RX antenna called the DHDL - or "Double Half Delta Loop". I will comment on my personal experience using this antenna for RX on 160m - but for those who want to read all about construction details, may I refer you to doing GOOGLE searches on: AA7JV - George Wallner who designed this antenna some years ago OK1RR - who has a paper out there on its design DH1TW - who also has a paper out there on its design ++++++++++++++++++++++++++ Basically during my talk at the Topband Dinner I divided the universe of 160m Dx'ers into two simple camps: "THE HAVES" - meaning those of us with lots of LAND, no zoning RESTRICTIONS and RESOURCES "THE REST OF US" - meaning those of us with small parcels (something like an acre or less) and perhaps a single tower from 70-90 feet in height. On the XMIT side - I noted that it is advisable for both camps to be VERTICALLY POLARIZED with your xmit antenna. HAVES - should aspire to multiple vertical radiators in combination in order to have: GAINDIRECTIVITYA HIGH "RDF" or "receiving diversity factor" - 12db or more In this case, one can probably listen on their XMIT antenna and do well. This can be supplemented with long or phased beverages in a few key directions THE REST OF US - can achieve vertical polarization with a simple inverted L - (this is a simple antenna and easy to make work) OR - one can shunt feed their 70-90 ft tower with yagis on top for top-loading However, in both of these cases RADIALS are required - (I prefer those on GROUND - but some like to try elevated radials) - this is a matter of personal preference. In both cases - you need a cooperating XYL who may or may NOT LIKE radials in their garden or running through their front yard! If Radials are not possible - the K2KQ DOUBLE "L" which does NOT require radials - is a great solution because it provides vertical polarization and can be hung off the side of an 80 ft tower or a tree with dacron cord - and this has proven to be a very decent xmit antenna for DX purposes. Complete details on the K2KQ Double L can be found on the YCCC.org website. You will find this antenna is quite easy to install. My wife and I hung one of a 64 ft Rohn-Spaulding Ax tower at VE2CSI in ZONE 2 in 2019 and managed to give 26 Ja stations their ZONE 2 on 160m - this was the first time any JA station had worked ZONE 2 in over 25 years - so I can report that this antenna really does work very well for DX'ing on 160m as a XMIT antenna. ++++++++++++++++++++++++++ So now then - What works on 160m RX "FOR THE REST OF US" - who are not lucky enough to be a HAVE with lots of land and resources? For me, it is the AA7JV DHDL ***without question*** and I will next comment on my personal experiences with this antenna. 1) In 2019 K1LZ and I were at V84SAA in Brunei and we needed an RX antenna aimed at EU. We had only 100 feet of beach available in that direction and we put up a DHDL right on the beach. Its spacing at 71 feet between twin fiberglass supports was perfect and BOY DID IT WORK! I managed 2,800 CW qso's with Europe listening on that antenna over the course of 10 days time. 2) My good friend 35 miles DUE WEST of me in Duxbury, MA is Don GREENBAUM N1DG. Don told me about his DHDL right after he had worked S2 out from under me some years ago - when I could not hear a thing on the QRG. Don also worked KRISH W4VKU when he was at VU4 in NOV 2024 - Don managed to hear him - I was right there listening on the QRG and did NOT. Boo Hoo again! 3) Fast Forward to TODAY: This past year I installed two DHDL's for 160m RX - the first was aimed roughly at CN8. This past winter I could copy ZS1C almost every night at his SR peak - and I compared DHDL copy to that of a K7TJR 4sq Rx array and also to an 850 ft beverage aimed at 140 degrees. The DHDL provided similar signal levels to the other two Rx antennas - night after night. OK1CF was always booming LOUD on the DHDL every night when Karel was on the air each evening. In March when VADYM UT6UD was on from 3Y0K each night on 1.835 he was good copy on the DHDL and my wife N1QV and I managed to work him pretty easily. THE DHDL was similar copy to my 850 ft beverage aimed at 140 degrees - even though the DHDL was not aimed directly at 3Y0K it provided workable copy at his SR peak. ++++++++++++++++++++++++ So what do you need to try a DHDL? a) (2) fiberglass mast supports 30-32 feet or so b) 71 feet of clear land to a height of about 32 feet c) A feedpoint matching xfmr to match 50 ohm or 75 ohm line to a DHDL feedpoint impedance of about 900 ohms d) A 900 ohm termination resistor e) A roll of HOME DEPOT #14 THHN stranded wire (or equivalent) In my personal case, as a BANKER and **not** a double EE, I needed help with the feedpoint transformer - as this usually is done using a binocular core and some fine enamel covered magnet wire. I reached to Tim K3LR for this and he had Greg Ordy W8WWV in the DXE engineering department wind me some transformers suitable for 50 ohm and 75 ohm line. 50 ohm line requires an 18:1 ratio and 75 ohm line needs a 12.5/1 ratio. Basically K3LR and DXE is intimately familiar with the DHDL and in a position to help those acquire what is needed to build and install one. My sense at the moment is that this antenna may not be all that well known - but for me, I am completely sold on it - as it solves my problem on something like 3/4 acre of usuable land for 160m antennas. One last point: Here I have tried almost all of the compromise 160m Rx antennas that are out there. This means the PENNANT, the FLAG, the EWE and the BOG. All of these antennas are negative DBI gain Rx antennas which means that you do NEED a TON of Rx pre-amplifier gain to make them hear well on 160m. THE DHDL ALSO NEEDS LOTS OF PREAMPLIFIER GAIN IN ORDER TO HEAR WELL!! You cannot just hook up a feedline to your RX and expect it to work its magic. Here I use an old AMECO PLF2 or a Gary Nichols KD9SV 160m preamp - which is then coupled into the RX - and I can vary the gain as needed using either preamp, or BOTH and sometimes the internal PREAMP in the Rx as well - depending on the prevailing conditions and noise on the band. So CAVEAT EMPTOR - preamp gain is IMPORTANT with a DHDL and a MUST!! NOTA BENE!! That said - it is worth trying a DHDL on RX if you are not a "HAVE" - and are seeking something simple on160m Rx hat might just work well for you. One final word of CAUTION from George Wallner AA7JV himself. George says "IT AIN'T A BEVERAGE" and he is right on with that statement. But I think he might have been thinking about a 1000 footer or something even longer than that length. Here at K1ZM - My take on the DHDL is that it performs about as well as a 600 ft beverage - and that's good enough for me to hear well on Topband in most cases. My second DHDL is aimed at the CENTRAL Pacific - installed less than a month ago - and it hears extremely well out that way - equal performance to my EU DHDL is what I would estimate after one month's usage and experimenting with them both this past weekend on 80m in CQ WPX CW. And the PACIFIC DHDL was clearly showing directivity when I would switch over to it versus the EU DHDL. Anyway - hope this is of interest to those out there on smallish properties. It's a several hour project once all the parts are on hand. My second one went up in about 3 hours time. 73 and thanks for the bandwidth! Jeff K1ZM/VY2ZMCape Cod Mass. Email: [email protected]
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