Figure 2  CQ21  21 Element Curtain Quad for 1296 MHz.

Figures 2a and 2b.  These drawings of CQ21 were created by 4nec2.  The dimensions of this antenna can be found in the program listing below and are repeated here for convenience.

All wires are #12 copper, with radius of 0.0404 inch.

All vertical wires are h = 6.08 inches long.

The center column of horizontal wires are l0 =  1.08 inches (read this as l zero is 1.08 inches).

The columns of horizontal wires next to the central column are l1 =  3.75 inches.

The next columns are l2 =  4.50 inches.

The outside columns of horizontal wires are l3 =  4.00 inches.

Figures 2c and 2d.  These plots for the CQ21 antenna were created by 4nec2 using the program below.

CM   CQ21  21 element Curtain Quad from W1HBQ

CE This program is written in 4nec2

SY l0=1.08      'The 21 horizontal wires represent 21 elements

SY l1=3.75      'All dimensions are in inches

SY l2=4.50      'All wires are #12 copper

SY l3=4.00

SY h=6.08       'The vertical wires are all the same length

SY y0 = .5 * l0

SY y1 = y0 + l1

SY y2 = y1 + l2

SY y3 = y2 + l3

SY z0=0

SY z1 = h

SY z2 = z1 + h

SY z3 = z2 + h

GW      1          11        0          y0        z3         0          y1        z3         0.0404

GW      2          2          0          0          z2         0          y0        z2         0.0404

GW      3          11        0          y1        z2         0          y2        z2         0.0404

GW      4          11        0          y0        z1         0          y1        z1         0.0404

GW      5          11        0          y2        z1         0          y3        z1         0.0404

GW      6          2          0          0          z0         0          y0        z0         0.0404

GW      7          11        0          y1        z0         0          y2        z0         0.0404

GW      8          11        0          y0        -z1       0          y1        -z1       0.0404

GW      9          11        0          y2        -z1       0          y3        -z1       0.0404

GW      10        2          0          0          -z2       0          y0        -z2       0.0404

GW      11        11        0          y1        -z2       0          y2        -z2       0.0404

GW      12        11        0          y0        -z3       0          y1        -z3       0.0404

GW      13        13        0          y0        z3         0          y0        z2         0.0404

GW      14        13        0          y0        z2         0          y0        z1         0.0404

GW      15        13        0          y0        z1         0          y0        z0         0.0404

GW      16        13        0          y0        z0         0          y0        -z1       0.0404

GW      17        13        0          y0        -z1       0          y0        -z2       0.0404

GW      18        13        0          y0        -z2       0          y0        -z3       0.0404

GW      19        13        0          y1        z3         0          y1        z2         0.0404

GW      20        13        0          y1        z2         0          y1        z1         0.0404

GW      21        13        0          y1        z1         0          y1        z0         0.0404

GW      22        13        0          y1        z0         0          y1        -z1       0.0404

GW      23        13        0          y1        -z1       0          y1        -z2       0.0404

GW      24        13        0          y1        -z2       0          y1        -z3       0.0404

GW      25        13        0          y2        z2         0          y2        z1         0.0404

GW      26        13        0          y2        z1         0          y2        z0         0.0404

GW      27        13        0          y2        z0         0          y2        -z1       0.0404

GW      28        13        0          y2        -z1       0          y2        -z2       0.0404

GW      29        13        0          y3        z1         0          y3        z0         0.0404

GW      30        13        0          y3        z0         0          y3        -z1       0.0404

GX       100      010                                          'symmetry in y direction

GS       0          0          0.0254

GE       0

LD       5          0          0          0          58000000        0          'copper wires

EX       0          6          1          0          1          0

GN      -1

FR       0          1          0          0          1296    0          'frequency is 1296 MHz

EN