Antenna testing - 202 aircrafts simultaneously

Coco is very alluring. It is very easy to make. The problem shows up only when it is put to service, and results are far less than expected or claimed. Only a small number of lucky ones endup in a good Coco, majority ends up in a poor coco & associated frustration.

Coco is very easy to make, but hard to get right.
Antennas with a 1/4 wavelength whip (67 to 69 mm for 1090 Mhz) are easy to make and easy to get right, and good for beginners.

It seems you made an antenna similar to “EASY ANTENNA # 1 : SPIDER” of the thread:

Three Easy DIY Antennas for Beginners.

You can see the photos there.