CM Circular skeleton Slot Antenna for 2m. at 145MHz, SWR 1:1.48, Peak gain 6.57dBi
CM By Roger Walker, GW6HRU
CM
CM Notes: (Because I can never remember these)
CM Wire Arc Specification (GA):
CM GA {ID} {NS} {AR} {A1} {A2} {RAD}
CM {ID} Tag number assigned to all segments of the wire arc.
CM {NS} Number of segments into which the arc will be divided.
CM {AR} Arc radius (center is 0,0,0 and is about the y axis).
CM {A1} Angle of first end of the arc
CM {A2} Angle of the second end of the arc.
CM {R} Wire radius.
CM Note: The angles are in degrees, around Y-axis, starting from x=0 in a left-hand direction (anti-clockwise)
CM
CM Coordinate Transformation (GM):
CM GM {II} {RP} {RX} {RY} {RZ} {SX} {SY} {SZ} {ID}
CM {II} ID Increment - What value to add to the created ID(s)
CM {RP} Repeat count, 0=Move
CM {RX} Angle in degrees to rotate about the X-axis. +ve = right handed
CM {RY} Angle in degrees to rotate about the Y-axis. +ve = right handed
CM {RZ} Angle in degrees to rotate about the Z-axis. +ve = right handed
CM {SX} Linear shift in X
CM {SY} Linear shift in Y
CM {SZ} Linear shift in Z
CM {ID} ID of segments to move/repeat, 0 (or missing) means all IDs
CE
SY R=3.00 'Loop aspect ratio (bigger = less height/more diameter)
SY K=0.855 'Velocity modifier for wire and ground proximity
SY F=0.31 'Feed point ratio (around circumference
SY W=0.0075 'Wire radius (15mm diameter)
SY H=5 'Height above ground
SY CL=K*299.792458/145.0 '1 wavelength
SY CH=CL/(1+R) 'Height
SY CC=2*R*CL/(1+R) 'Circumference of each loop
SY CR=CC/(2*PI) 'Radius of loops
GA 11 6 CR 0 360*F W ' Arc from 0 to 360*F
GA 12 18 CR 360*F 360 W ' Arc from 360*F to 360
GM 0 0 90 0 90 0 0 H 0 ' Move Both ARCs to horizontal, at 0,0,H
GM 10 1 0 0 0 0 0 CH 0 ' Copy Both ARCs to horizontal, at 0,0,H+CH (as ID+10, so 21 and 22)
GW 2 11 0 CR H 0 CR H+CH W
GW 1 11 CR*sin(360*F) CR*cos(360*F) H CR*sin(360*F) CR*cos(360*F) H+CH W
GE 1
LD 5 0 0 0 58000000
GN 2 0 0 0 4 0.003
EK
EX 0 1 2 0 1 0 0
FR 0 0 0 0 145.0 0
EN