A year ago I thought about renovating one of the yagi by starting designing and building a two crossfeed multi-monoband elements.
Currently there is no such thing on the market to compare my project so everything comes up on paper and simulations and no one can know if it will be a success or failure until the antenna will be ready to be tested!
The simulations, at a first stage, only concern bands 10-12-15-17m leaving standby the 20m that will be optimized during the antenna test on the field.
Below are the plots of the various bands simulating the antenna at 10mh from the roof, real height of the future installation :
Well, the simulations have been made and I saw that croosfeed make a similar gain like a 3el as I imagined, now is the time to start building the hardware part.
The boom will be around 2.2m long and the two elementes 5.1m and 5.5m for the element feed like reflector.
The 50 Ohm feed arrive at a box on the middle of the boom where there are the 50 Ohm feed split (25 Ohm each element) and the control cable split that will be necessary to activate at the same time 2 vacuum relays each elements (Siemens VR-311 will allow me to run QRO).
to be continue…