Re: Electric aerial spider
I rebuilt mine a month ago. Apart from the sticky tape and twisted wire bodge which was causing intermittent problems, it was very "sticky" when it actually worked.
There is a nylon toothed band that runs up the centre of the hollow sections and extends/retracts the aerial. This is driven from the motor, and if there's any resistance, nylon against nylon jumps the teeth.
A lot of aerials aren't quite straight after a few whacks over the years, and maybe excessive motorway speeds can put them out of straight, so the first thing is to carefully make it straight. Squint down it to check for trueness.
Then use WD40 to clean it, but wipe the excess off so it's nice and clean afterward. A few ups and downs can bring out more dirt so repeat the cleaning a few times.
It should then go up and down smoothly. If it's still bad then take it apart, nothing goes ping and it's quite simple inside.