This is a great L1/L2C/L5 GPS antenna jig for making a Quadrifilar Backfire Helical Antenna.

The design is tuned to 1200 MHz, which is directly between the L2C and L5 GPS bands, but still gets great coverage on L1.

Assembly instructions and background on the antenna design can be found at the links below.

http://jcoppens.com/ant/qfh/calc.en.php
https://www.pinterest.com/pin/525373112773545290/

Creality

Ender 3 Pro

No

Yes

0.2

50%

PETG may cause interferance issues on the internal components, but my test unit performed well using PETG. PLA will probably yield better results.