>First off are the long whip antennas (I think they are
>102") really that much better then the "regular" CB
>antennas?
You tell me. Which is better? A very tall antenna that has
more area to catch the signals.......or an itty-bitty short one? 
However a full-size antenna is a pain for garages and under bridges. 
BTW: The short ones are the same size electrically because there is a
coil inside that makes up the difference. The coil makes the antenna
look OK to the radio, but is a compromise RX and TX-wise.
It depends on what you want to do. Short-range communications
will work fine with a little one. If you are way out in the Boonies
a full-size antenna can make a big difference.
>Most of the long whips I've seen are tied down.  Does
>this affect their transmitting range or direction?
OH YES! The radiation pattern on a vertical antenna (CB) is like a
donut on a stick. You want that donut to be flat so all the signals
go out forwards, backwards, left and right.....
If you tie the antenna down in a loop you are turning the donut somewhat
sideways and some of your power is going up and down. You are wasting 
signal (unless you like talking to the moon and the ground. ).
Also you are now putting the antenna right against
your car and that will do strange things to the pattern of radiation and
the SWR. 
Will it work that way? Sure. 
Will it be "right"?    No. 
What do you want to do? Short-range or As-far-As-Possible?
>There have been several times when I have knocked over
>the antennas when I went under a 'low bridge', always
>at slow speed.  To me this is a good think.  I hate to
>think what kind of damage would have been done to
That what the spring is for at the base of a full-size CB antenna.
>either the antenna or the roof if the antenna had be a
>permanent mount.
Yup. That's one of the three advantages of a magmount.
1) No holes needed
2) Transferable between locations
3) Will fly off without damaging the car (usually).
On #3....Amateur Electronics here in Milw carries a *BIG* *BIG* magmount 
ase.
It has three *HUGE* magnets on in and you get a hernia taking it off the roof
of your car. I think if THAT ONE got hit you might see some damage to the
roof.
KG9EV
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