How to Stack two Triband Yagis
Jun 18th 2021, 18:08 | |
WB5EMXJoined: Aug 25th 2016, 23:32Total Topics: 0 Total Posts: 0 |
I have a couple of Triband Yagis for 10, 15, and 20 meters. I'd like to stack them. Is this when one should use a Wilkerson Power Divider? How far apart should they be placed? Suppose I purchase the kit to run one on 30 meters. Can I run them paired up except for 30? Has anybody done this before? What kind of spacing was used, and what technique was used to harness them? Thanks. Bob, WB5EMX |
Jun 19th 2021, 08:19 | |
W1VTSuper Moderator Joined: Apr 4th 1998, 00:00Total Topics: 0 Total Posts: 0 |
Dean Straw discusses this topic in the ARRL Antenna Book. It is a complicated topic but the Antenna Book is one of the best starting places to look. As far as I know Dean has retired and is not taking questions. It is hard because it requires compromise and that is something that seems to be out of fashion these days. Someone at a local contest club may have the expertise to make reasonable suggestions for what you need where your live. Stacks are most useful for hams with tall towers in times of high solar activity that allow high angle DX paths. At solar minimum, as we are now, most hams just need a single antenna as high they can get it. A single Yagi at 70 ft is more practical for most hams than a stack on a 100 or 200 ft tower. Dean wrote the HFTA program that comes with the ARRL Antenna Book. He also compiled propagation statistics over a solar cycle to help choose optimum stacking heights. k6tu.com is the best source for terrain data. As far as I know the government databases terrain used in Deans' time are no longer usable by hams. Zak W1VT ARRL Senior Lab Engineer |
Jun 19th 2021, 22:40 | |
WB5EMXJoined: Aug 25th 2016, 23:32Total Topics: 0 Total Posts: 0 |
Incredible response, VT. Answered my question with surgical accuracy. I'll dig around in the Antenna Book, do a bit of self educating. |
Jul 22nd 2021, 16:29 | |
WB5EMXJoined: Aug 25th 2016, 23:32Total Topics: 0 Total Posts: 0 |
Apparently this is done more frequently in Europe than in the U.S. Using two yagis in parallel tends to reduce QSB. |