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Antenna Plans

Build the 3 x 5 Elements 2m/70cm Dualband Yagi

Build your own 2m/70cm 3 Elements VHF by 5 Elements UHF Yagi antenna with excellent gain for both VHF and UHF operation. This antenna is designed for amateur band frequency for both VHF (2m) and UHF (70cm). The antenna has good reflection coefficient and VSWR ratio @ 1.2:1 at center frequency and 1.7:1 at band edge.

Antenna Specs from 4Nec2

VHF Gain: 7.25dBi @ 145Mhz
Beamwidth: 114° degrees
Front to Back Ratio: 14.1dB
VSWR: 1.0:1

Expected pattern VHF

UHF Gain: 10dBi @ 440Mhz
Beamwidth: 60° degrees
Front to Back Ratio: 14.4dB
VSWR: 1.2:1

Expected pattern UHF

Building Video 3 Elements by 5 Elements 2m/70cm Dual band Yagi including Tuning

Material list for 3×5 Elements Dualband Yagi

1. 1″ X 0.5″ Rectangular Aluminum tubing for the boom
2. 3/8″ Aluminum tubing for antenna elements
3. 1cm Outside diameter antenna tubing for elements holder
4. 2pc SO239 connector
5. Pop rivets / Rivet tool
6. #12 AWG Copper wire with insulation (12″for Gamma match)
7. Soldering iron
8. 10pcs Stainless steel nuts and bolts 20mm length 3mm diameter
9. 1pc, Butterfly nut and 1 bolt 18mm length 3mm diameter
10. Aluminum plate 0.5mm thickness
11. 4 X 2″ Aluminum tube for bracket
12. Collapsible tube (shrinkable tubes)

Gamma Match for Dualband Yagi