My power antenna worked fine when I bought the car but when I set it up for the suspension refreshing I put the antenna down, now it will not go back up. The motor works, in either direction. I was going to just jump into it, but wanted to check with the experts first in case it is always the sample problem...

You'll be well served to pull the antenna assembly and disassemble for cleaning. Lots of water and crap gets in it over the years. Lube the areas that need it w/water resistant grease. You may also find the white "snake" that actually drives the mast has become unattached from the reel or has broken. It is not a difficult thing to do and be sure to unplug the water drain hose.

Clean it if the antenna, if plastic shaft broke I came up with a way to use heavy trimmer sting to fix it. I posted the information on this site this year

I've seen commercials about this. Try taking some Extendz, from what I hear it gets antennas to go up.

The antenna allows water to flow down the plastic mast to a drain on the bottom well that gets gonked up. This can cause the shaft to snap. On my first Z I'd spray a little penetrating oil in the antenna to help prevent this after I rebuilt it.