First produced in 1993, the C-3 is the first trapless tribander. It uses 7 full size elements on a 18’ boom for full coverage of the 20-15-10 mtr bands, plus having gain on 17 and 12 mtrs, too. All that is needed is a 1:1 balun (like the Force 12 B-1) or RF choke and you are on the air with 5 bands! The core of the C-3 is three monoband Yagis for 20, 15, and 10 mtrs. They are arranged so that all 7 elements work together for great performance. This technique is called, “forward stagger.” The driver cell is a patented Force 12 open sleeve, with the coax attached directly to the 20 meter element. The 15 and 10 mtr drivers are parasitically excited. The C-3 comes in a 4’ box, ideal for DXpeditions and is perfect for everyone desiring peak performance. For those who want more, a stack of C-3’s is simple to install and works great, providing 2-3dB more gain on all bands.
Antenna
|
Boom Length (feet)
|
Wind Load
|
Frequency (MHz)
|
Gain @74’1
|
Net Gain
|
F/B Ratio
|
VSWR (max)
|
Turning Radius
|
Wt.
(lbs)
|
Mast Torque
|
C-3
|
18’
|
5.5sqft
|
14.000-14.350
|
12.6dBi
|
4.6dBd
|
15dB
|
<1.6:1
|
19.8’
|
32#
|
<280in/lb
|
7 elements
|
|
|
18.068-18.168
|
10.3
|
2.3
|
7
|
~2.8:1
|
|
|
|
(1)
50 ohm feedine
|
|
|
21.000-21.450
|
12.8
|
4.8
|
17
|
<2:1
(425 kHz)
|
|
|
|
|
|
|
24.890-24.990
|
10.1
|
2.1
|
11
|
<3.2:1
|
|
|
|
|
|
|
28.000-29.700
|
12.5
|
4.4
|
18
|
1.5 MHz
|
|
|
|
Specifikation C3.pdf