Lotlot built a GP for the 144 MHz band at the request of a customer! I had leftover 1/4 Mobil Whip on hand, so I offered it to him. He made it himself while looking at "Wire Antenna" and "Revised New Edition, Introduction to Handmade Antennas" published by CQ Publishing. Of course I translated, interpreted, advised...
I explained that tilting the radials is not just design, but also impedance matching
Lotlot's first self-made antenna shining in the sun