Moxon Antenna for 2m

3/8 " aluminium tubular elements, left over from a cannibalised VHF TV Yagi beam, were used to fabricate this 2m Moxon Antenna.

2m Moxon Antenna

Screw joints became a necessity since the elements were not long enough. The ends were flattened and drilled for the purpose.

A scrap plastic handle came in handy for the spacers. It was easy to cut it, drill the fixing holes and make a recess for the BNC socket.

Dimensions were obtained using the 'MoxGen - MOXON Rectangle Generator'.

For vertical polarisation, this antenna is directly mounted on a PVC pipe mast with a screw through each spacer.

Preliminary checks showed that this antenna is as good as, if not better than, my 'simple 2 element array'. Both, being 50Ω antennas, are capable of outperforming even a 3 element array with its associated matching problems.

Related post: Simple 2-element Array for 2m
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Simple 2-element array for 2m

This array was homebrewed using four 18" long telescopic whips and a length of ¾" diameter thick-walled CPVC water pipe.

Data for the 2-element array was obtained from an old ARRL Handbook.

Dimensions in inches: Driven Element - 5540/f MHz, Director - 5263/f MHz, Spacing - 2750/f MHz.

The spacing close to 0.25λ would result in a good match for 50Ω coaxial cable.

Maximum gain would be possible with a director at 0.1λ or a reflector at 0.15λ. However matching issues related to the very low radiation resistance would then have to be tackled (F.C.Judd G2BCX in '2 meter Antenna Handbook').

2m 2-element array

The shorter length of the telescopics was made up with spacers which also served as mounts for the elements. The spacers were made using scrap bakelite strips. Self-tapping screws were used to fasten the elements to the CPVC pipe. A BNC socket was mounted at the feed point and wired to the elements.

2m 2-element array - close-up (element folded)

The array is easy to carry as the elements can be 'telescoped in' and folded. Hence it lends itself to portable operation or direction finding.

Theoretical gain for this array is 3dB.

Preliminary on-the-air checks for gain, front-to-back ratio and null, were encouraging.

Related post: J-Pole Collinear for 2m
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