View Single Post
  #8   Report Post  
Old October 3rd 10, 03:34 PM posted to rec.radio.amateur.antenna
John Ferrell[_2_] John Ferrell[_2_] is offline
external usenet poster
 
First recorded activity by RadioBanter: May 2009
Posts: 101
Default Channel Master CM4228HD Antenna

On Sun, 03 Oct 2010 11:46:24 GMT, "Frank"
wrote:


"John Ferrell" wrote in message
.. .
I would like to model the Channel Master CM4228HD Antenna with EZNEC.
It looks like a good deal to me at its price.

I need screen to Bow ties distance

length of bow ties

I think the distance between the bowties will be either 1/4 or 1/2
wave (from picture)

I think the included angle in each of the bow ties is about 30 degrees
as pictured.

The phasing lines are obvious from the picture.

There is a picture at
http://www.digitalhome.ca/forum/showthread.php?t=95467

Of course I will share the model!

John Ferrell W8CCW


The following NEC code is for a measured 2 bay bow-tie. Should be the
same as an 8 bay model.

Frank (VE6CB)


CM UHF TV Antenna (Measured dimensions).
CE
GW 1 12 0 1 0.25 0 7 1.5 0.081
GM 1 1 0 180 0 0 0 0
GM 2 1 0 0 180 0 0 0
GM 4 1 0 0 0 0 0 8 ! End of two dipole array.
GW 9 17 0 1 -0.25 0 1 8.25 0.081 ! Parallel transmission line.
GW 10 17 0 -1 -0.25 0 -1 8.25 0.081 ! Parallel transmission line.
GW 11 4 0 -1 4.25 0 1 4.25 0.081 ! Feedpoint segment.
GW 12 36 -8 -9 -2 -8 9 -2 0.081 ! First horizontal grid element
GM 1 12 0 0 0 0 0 1 12 1 12 36 ! Creats 12 horizontal grid elements
GW 25 24 -8 -9 -2 -8 -9 10 0.081 ! First vertical grid element
GM 1 9 0 0 0 0 2 0 25 1 25 24 ! Creats 9 vertical grid elements
GM 0 0 0 0 0 0 0 120 ! Moves entire structure 10 ft high
GS 0 0 0.025400
GE 1 -1 0
GN 2 0 0 0 13.0000 0.0050
FR 0 1 0 0 635 1
EX 0 11 2 0 1 0
LD 5 0 0 0 2.5E7
RP 0 1801 1 1000 -90 0 0.10000 1.00000
EN


This example may be what it takes to get me to get onboard with NEC.
EZNEC has me spoiled!

So little time and so many projects...

I love my busy, cluttered life and all the puzzles to solve!
John Ferrell W8CCW