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Antenna Plans

2×4 2m/70cm Compact Cross Yagi Sat Comm Antenna

Compact satellite communication antenna

This antenna built is similar to the 2×3 Compact Cross Yagi antenna with the addition of additional element on the UHF side. We have similar measurements for all the elements.

Antenna measurements and mounting guide

Download the PDF document here

Materials list

1″ X 1″ Rectangular Aluminum tubing for the boom (cut to length)
3/8″ Aluminum tubing for antenna elements (cut to length)
2pc SO239 connector
#12 AWG Copper wire with insulation (12″for Gamma match)
Soldering iron
6pcs Stainless steel nuts and bolts 30mm length 3mm diameter
6pcs Stainless steel nuts and bolts 30mm length 3mm diameter
1, Butterfly nut and 1 bolt 18mm length 3mm diameter
Aluminum plate 0.5mm thickness
Collapsible tube (shrinkable tubes)

4Nec2 data analysis

Antenna gain, beam width and predicted pattern spit out by 4Nec2 antenna modelling software

Antenna pattern for the VHF side

Antenna pattern for the VHF Side

Antenna pattern for the UHF side

Antenna pattern for the UHF side

Vector impedance analyzer frequency response data

This is the result of impedance analyzer testing for 2×3 elements cross yagi. Obtainable SWR is around 1.2:1 at the center frequency antenna reflection coefficient is at -24dB at VHF and -19dB at UHF. Pretty usable antenna, as you can see as well, the data spit out by 4Nec2 with regards to SWR on VHF side is close enough, I just directly cut the elements and assemble it with respect to the antenna measurement for the UHF side it was compensated with the use of gamma matching and correct length of the phasing harness.

Actual testing of the antenna

This is actual testing of the antenna see the video for SO-50 satellite

and this video is for AO-91 satellite contact.