I was look for a small compact dual band antenna for 2m /70cm. I came across a design by DK7ZB and can be found here http://www.qsl.net/dk7zb/Duoband/4+5_2m-70cm.htm.
The boom is square 19mm x 1m and uses 10mm elements. The boom clamps are 3d printed using black PLA.
Below are the measurements using 8mm and 10mm tube. The radiating element is constructed from 12mm tube for both versions.
|El.-No.||Element||Position||Length (8 mm)||Length (10 mm)|
|1||Reflector for 2m||0 mm||1013 mm||1011 mm|
|2||Reflector for 70cm||110mm||343 mm||332 mm|
|3||Radiator 2m and 70cm||260 mm||973 mm (12 mm)||973 mm (12 mm)|
|4||Director 1 70cm||308 mm||319 mm||316 mm|
|5||Director 2 70cm||440 mm||312 mm||310 mm|
|6||Director 1 2m||465 mm||919 mm||911 mm|
|7||Director 3 70cm||750 mm||267 mm||261 mm|
|8||Director 4 70cm||965 mm||283 mm||278 mm|
|9||Director 2 2m||985 mm||879 mm||870 mm|