It would depend on the frequencies you are monitoring. Duckies tend to be
optimized for certain ranges (often leaving dead spots or nulls in other
ranges) whereas the Discone or Scantenna are wideband designs. At UHF, the
loss in the coax feed line from the external antenna could tend to reduce
the signal available at the receiver as compared to the directly-mounted
ducky (depending on coax quality and length of course). Another thing to
consider is that an external antenna with some height could overload the
receiver, making it seem like it does not work as well. Adding an
attenuator helps this problem.
So as you can see, there are more variables than just antenna type and
height. Frequency, type, length and impedance match of the antenna feed
line and receiver quality are among the others that need to be considered
before you could draw a proper conclusion.
All that aside, I think a discone or Scantenna would probably be better in a
> Question regarding handheld scanner aerial (the ***-ducky kind that
> with unit):
> Assuming that I have all of the following 3 aerials at the same height,
> would there
> typically be "much" of a difference between what the handheld would hear
> with it's own aerial, compared to, e.g.,
> an external R/S Discone or Scantenna aerial connected to the scanner ?
> [again, all 3 at same location and height]