Whereas the radiating element of screwdriver antennae is tunable over
a wide frequency range, is it necessary to employ a 1/4 wave radial
for each band that it is proposed to work?

gareth wrote:
Whereas the radiating element of screwdriver antennae is tunable over
a wide frequency range, is it necessary to employ a 1/4 wave radial
for each band that it is proposed to work?

The physical type of a vertical radiator close to ground makes no difference
in regard to radials or grounding.

A screwdriver antenna is just a vertical with a variable loading coil.


--
Jim Pennino

In message , Jeff writes
On 12/02/2016 23:26, gareth wrote:
Whereas the radiating element of screwdriver antennae is tunable over
a wide frequency range, is it necessary to employ a 1/4 wave radial
for each band that it is proposed to work?


Obviously not as most screwdriver antennas are used in mobile applications!!

Do you mean to say that the 132' wire (with a brick on the end), that I
used to trail behind my car when operating on 160m, wasn't necessary?
--
Ian

Ian Jackson wrote:
In message , Jeff writes
On 12/02/2016 23:26, gareth wrote:
Whereas the radiating element of screwdriver antennae is tunable over
a wide frequency range, is it necessary to employ a 1/4 wave radial
for each band that it is proposed to work?


Obviously not as most screwdriver antennas are used in mobile applications!!

Do you mean to say that the 132' wire (with a brick on the end), that I
used to trail behind my car when operating on 160m, wasn't necessary?

Did you get out further than a quarter mile, though?

--
STC // M0TEY // twitter.com/ukradioamateur