peter
i dont understand your problem
all you have to do is pick one of the samples i send you and create the
antennas from the design make 3 or 4 of them and make them all alike
from one set of plans and you will be fine i would suggest building
something like the 432mhz one cause its closer to the freq you need
good luck
the next issue you will have is where to get the stuff to make the antenna