Track ADS-B from within a plane

you can put a single wire of the exact length (i think it’s something of 55-60mm) directly into the antenna socket of the stick. I’ve seen this somewhere here in a forum post.

For getting the signal of the own flight it should work.
@abcd567 built a lot of antennas and he should have the exact dimensions.

EDIT: Maybe you find something usable here: