Gyro Doctor
Electronics Tech for over 45 years
On a bird that big you might consider going half-wave (24.6 - 26 mm) instead of quarter-wave
If you want to get fancy make that a dipole too:
Instead of just cutting off the braided shield strip only the insulative outer covering, then fold back the braid onto the unstripped coax.
Finish the end of the braid with some solder to prevent it from unraveling .... viola .... 5.8 GHz 1/2 wave dipole antenna !
Note: Home making antennas comes at the risk of damaging the transmitters they are attached to.
That is why I always deploy such items as RECEIVER antennas FIRST and tune them for optimum reception before mounting them on any transmitter.
Tuning it involves removing about a 1/2 mm at a time from the radiating element (inner conductor) until the best reception is noticed for the frequency of choice.
The problem is that you have to pass that optimal point (length) by continued improvements up to the peak, after which the performance then begins to drop off again
as more radiating element is removed, thereby realizing where the peak was.
With respect to the braid, rather than cutting, just lapping it back over onto it's self is sufficient (and also makes for easier soldering too). Adjustments to the braid's length should go along with those made to the inner wire to maintain the dipole's symmetry.
Given this is a trial and error process, don't bother "dressing" the braid until you've found the length you desire and prepare a few pieces of coax before you even start and write down the measurements as you go.
It's almost more complicated to explain what to do than the actual process of doing it, which is actually pretty easy.
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