Rob:
A typical 3/8 wl inverted-L antenna is about 65 feet
vertical and 125 feet horizontal or sloping back downwards at a slight
angle. This means that 2/3 of the wire is horizontal near the ground
and is a high angle radiator - semi NVIS - and the vertical part is
radiating at a low angle.
If I were to extend my 1/4-wave inverted-L to a 3/8-wave L, and tune
out the inductance with a fixed capacitor at the base, what would this
do to the broadbandedness of the antenna?
There is an old basic principle to remember about this, The fewer the
components in general, the broader the
Another rule for this is the lower the Q of the matching network the
greater the bandwidth.
Herb Schoenbohm, KV4FZ
On 5/7/2012 1:48 PM, Roy wrote:
If I were to extend my 1/4-wave inverted-L to a 3/8-wave L, and tune
out the inductance with a fixed capacitor at the base, what would this
I don't know how much bandwidth you could get with coaxial quarterwave
transformer (say, two quarterwave lengths of coax in parallel to transform
12 Ohm of an inverted L to 50 Ohm)?
In previous life I was used to use quarterwave 75 Ohm cable to broaden
bandwith of 80m dipole(s)...
73 Mirko,
Roy, you didn't specify the vertical length of your inverted-L but I'll
assume it is 50' and that your base-referred ground loss is 5 ohms.
Using NEC-2 for the 1/4 wavelength inverted-L I get a 2:1 VSWR bandwidth of
51 kHz. Note the base resistance at resonance is 18 ohms.
For the 3/8 wavelength
If I were to extend my 1/4-wave inverted-L to a 3/8-wave L, and tune
out the inductance with a fixed capacitor at the base, what would this
do to the broadbandedness of the antenna?
Inquiring minds...
Rob / KD8WK
___
UR RST IS ... ... ..9 QSB QSB - hw?
On 2012-05-06, at 2:42 PM, Rob Stampfli wrote:
If I were to extend my 1/4-wave inverted-L to a 3/8-wave L, and tune
out the inductance with a fixed capacitor at the base, what would this
do to the broadbandedness of the antenna?
Hi Rob,
The 2:1 SWR points on my extended 3/8-wave inverted
