rfoverlord,
I read your thoughts about the variable length mobile antenna's seals and getting dirty, etc. All things considered, it isn't as much of a problem as you might think. Sure, the inner shaft can get dirty, and the 'seals' will wear out, but normal maintenance takes care of those things easily. Can't comment about the 'HiQ' antenna, never saw one. But I've had one of the screwdriver type things and do know a little about them (one that definitely was NOT of the quality of the 'TarHeel' or any of the other commercially made ones).
The one 'problem' that was the biggest worry was the 'finger-stock' that was used to make contact with the moving coil. Easily solved, just use a spring 'wrapped' around the moving coil as the 'contact' instead. (Antenna Dark-Ages, as in when they first started showing up. The 'dirt' shield on the outside of the coil was also one of those 'brilliant ideas' of that 'age' in history. Remember those large plastic 'candy-canes' filled with Christmas candy at 'Wal-Mart'?? Yep, that's where they first came from - lol. Won't tell you where the 'spring' thingy came from, you wouldn't believe me anyway.)
- 'Doc