ORIGINAL: mcovalsk
If the coil is not properly designed (usually called antenna loading coil, which extend the physical large of the antenna ) has not other reason that save space. In fact is worst, the best is to make a square antenna ( or zigzag like pictures showing here) instead a small coil.
Well I did post the picture of the zig-zag antenna in a PZ III already in the second post in this thread. But I'm not sure I agree with the coil antenna being "the worst" unless you only meant if it was designed completely wrong itself, as many people have used them very successfully, getting almost as much range as the HL stock antennas.
It would be great if there were some verified tests showing results of the ranges people have gotten with their various types & positioning of their inside antennas.
I'd still like to hear input from any antenna expert on how the various internal antennas, if done correctly, should perform, & how important polarization of the signal is in regards to the type of antennas being used.
~ Craig ~