11-Meter Yagi. Seven projects


Here seven bullet-proof yagi, from 3 to 8 elements, from 2.5 to 19 meter boom. Bullet-proof, why? Anything is scaled to 11m from the 10-Meter ARRL project. All are designed with one goal in the mind, to maintain a solid gain and F/B and SWR ratio over the band.

So who wants to build one, should better buy the ARRL Antenna Book, he will learn a much more about aerials. Niggards, mail me and I'll try to help ;-)

These are supposed to be feed by gamma-match, and elements are (electrically too) connected to boom via U-bolts and aluminium plates. The big ones require you add a compensator, i.e. a dummy (plastic) element on purpose to compensate wind load. Won't to tire, more private if need.

Aluminium tubing is for all yagi the same, i.e. same diameters and, for inner section, also same length, while outer must have his own length depending on element and design.

So I will table only tip's length and element spacing.
Remember, if you're forced to use different diameter tubes, is maybe better to run computer again. Anyway with 12mm tips instead of 13mm the antenna shifts 100 Khz up, i.e. from 27.500 to 27.600

Software is, as usual, Eznec. Btw the "More graphics" images are by Yagi Analizer by K6STI Brian Beezley.

Try this first, if you want. It's a comparative analysis of gain you can expect by these aerials, 11 meter up over average ground, for 10-degree elevation angle. Remember please, this is not necessarily and always the max gain of each yagi ... Anyway here is the gap from 8-foot to 62-foot, 6 dB.

Excuse me for my English, enjoy, errors to dx11@bib.uniurb.it
Paolo 1839, July 28, 1999.



Three-element Yagi, 8-foot boom

More graphicstips, dia.1/2", 13mm.
reflector at 00.0"
00.00 m.		74.23", 189 cm
driver at 37.2"
00.95 m.		64.94", 165 cm
director 1 at 93.0"
02.36 m.		60.42", 154 cm



Four-element Yagi, 14-foot boom

More graphicstips, dia.1/2", 13mm.
reflector at 000.0"
00.00 m.		72.29", 184 cm
driver at 037.2"
00.95 m.		65.97", 168 cm
director 1 at 074.4"
01.89 m.		64.29", 164 cm
director 2 at 167.3"
04.25 m.		54.87", 140 cm



Five-element Yagi, 20-foot boom

More graphicstips, dia.1/2", 13mm.
reflector at 000.0"
00.00 m.		73.72", 188 cm
driver at 037.2"
00.95 m.		65.45", 167 cm
director 1 at 074.4"
01.89 m.		64.81", 165 cm
director 2 at 144.6"
03.67 m.		63.52", 162 cm
director 3 at 241.7"
06.14 m.		58.23", 148 cm



Five-element Yagi, 25-foot boom

More graphicstips, dia.1/2", 13mm.
reflector at 000.0"
00.00 m.		73.07", 186 cm
driver at 037.2"
00.95 m.		65.32", 166 cm
director 1 at 074.4"
01.89 m.		64.42", 164 cm
director 2 at 176.6"
04.49 m.		62.23", 158 cm
director 3 at 291.3"
07.40 m.		57.97", 148 cm



Six-element Yagi, 37-foot boom

More graphicstips, dia.1/2", 13mm.
reflector at 000.0"
00.00 m.		73.20", 186 cm
driver at 038.2"
00.97 m.		64.94", 165 cm
director 1 at 082.6"
02.10 m.		64.42", 164 cm
director 2 at 183.9"
04.67 m.		62.10", 158 cm
director 3 at 315.0"
08.00 m.		61.20", 156 cm
director 4 at 440.0"
11.18 m.		57.06", 145 cm



Seven-element Yagi, 49-foot boom

More graphicstips, dia.1/2", 13mm.
reflector at 000.0"
00.00 m.		72.81", 185 cm
driver at 038.2"
00.97 m.		65.45", 167 cm
director 1 at 076.4"
01.94 m.		64.81", 165 cm
director 2 at 175.6"
04.46 m.		62.10", 158 cm
director 3 at 309.9"
07.87 m.		59.52", 152 cm
director 4 at 468.9"
11.91 m.		59.90", 153 cm
director 5 at 588.7"
14.96 m.		57.06", 145 cm



Eight-element Yagi, 62-foot boom

More graphicstips, dia.1/2", 13mm.
reflector at 000.0"
00.00 m.		72.42", 184 cm
driver at 043.4"
01.10 m.		65.68", 165 cm
director 1 at 081.6"
02.07 m.		64.42", 164 cm
director 2 at 171.5"
04.35 m.		62.61", 159 cm
director 3 at 301.6"
07.66 m.		60.55", 154 cm
director 4 at 447.2"
11.36 m.		59.13", 151 cm
director 5 at 609.3"
15.48 m.		59.77", 152 cm
director 6 at 734.3"
18.65 m.		57.32", 146 cm