Yagi element holder for 20×20 mm yagi antenna boom.
With this element holder it is easy to attach a 6 to 12 mm element to a 20×20 mm yagi antenna boom.
Each type of element holder and used boom diameter entails a certain correction of element length:
For this element holder, use the following correction:
70 MHz = 2.3 mm (approximately)
144 MHz = 3.9 mm (elem. Ø 8 … 10 mm)
403 MHz = 7.1 mm (elem. Ø 6 … 10 mm)
432 MHz = 7.5 mm (elem. Ø 6 … 10 mm)
The elements should therefore be extended with the values from the list above.