Performance of C3S Antenna at N1EU

In August 1999, I installed a Force12 C3S tribander (2 active elements per band, 12ft boom) on
an AB577/GRC antenna mast at 50ft.  I conducted some informal testing with my good friend and one 
mile distant neighbor W2ZU.  Below is some data - did some comparison measurements of f/b ratio of 
his Force 12 C3 at 54ft with my C3S at 50ft by firing a few hundred milliwatts of RF at each other.
Used the S meter in a TS930 for signal strength measurements off the front and back of the beams.  
Repeated the tests with both ends transmitting, and swinging the beams on transmit and receive.  
I also did a quick comparison receiving W2ZU off a 5-band one element Lightning Bolt delta loop 
(horiz pol) with apex at 50ft.  Margin of error reading the meter and setting levels was probably
less than 2dB.


        f/b ratio dB
        C3      C3S       C3S gain over delta loop

20m     13       10         8

17m      3        2       -0.5

15m     12       13        10

10m     20       18         7


test frequencies: 28.3, 21.2, 18.1, 14.1 Mhz



Here's the SWR off the C3S:

20m  14.35  1.6
     14.135 1.1
     14.0   1.5

15m  21.45  2.0
     21.2   1.25
     21.0   2.0

10m  28.0   1.0
     28.275 1.5
     28.6   1.0
     28.85  2.0
(double null on 10m)


The C3S at a modest 50ft height has proven itself to be an incredible performer, especially considering
its 12 ft. boom length.  In the 2001 ARRL DX CW contest, it helped garner the highest single op multiplier count (521).
This little antenna quickly busted a lot of pileups in tough competitive situations.


Picture of C3S antenna at N1EU
Picture of C3S antenna in the snow at N1EU