First I'd like to encourage anyone to post models here.
I consider posting a model here virtually equal to placing it in the public domain.
Use any model that I post that you like for what ever purpose you like.
If you want to protect your model from others my advice is don't post it.
If I post work from someone else I will credit their work.
Starting out building models can be overwhelming ,but running an existing model is relatively easy
Just copy the "code" for the model paste into a text file and rename or save as XXXXX.nec move it to the models folder of 4nec2 and open it with 4nec2 (the little folder icon on the left).
Click the calculator icon or hit F-7 and pick far field pattern and then Generate.
At first I learned more from tinkering with other peoples models than anything else .
It's also nice to have a template that when you feel ready you can just paste in the wires ect. and not worry if you forgot a critical line or got them out of order.
I was going to just post free space models but it's easy enough to change to any ground desired.
By convention one always starts with the simple antenna first, a dipole perhaps?
No, I think I'll come back to dipoles later there are examples included in the stock models included at install.
I think I'll honor hommers efforts here and use his build of a moxon made from an old walker as the first model posted here. It is also scratch built with variables in mind and pretty easy to dissect and follow.
Model 1
Same Moxon above moderate real ground.
Many of my models are designed or modified to show the answer to some question (or try).
How far apart should I stack moxons ? Should I bother if I can only go up ?? feet?
What if I delay the feed to one of the antennas?
What about a staggered stack?
I never got this model to show the qualities it should be capable of. (great f/b ratio)
maybe I didn't try the right combination of stager and delay.
If any one finds a nice version of this post the SY values needed to change.
Wasn't real happy with the stacks I don't think it's worth the trouble .
Notice the first GW line
GW 1 9 0 -y 0+agl 0 y 0+agl 0.375
has the Z coordinates (both ends) of 0+agl obviously the zero is redundant it's a remnant of rapid modification with the new nec editor. I'll address that soon. I should have removed them but I didn't want to chance garbling the model, and they still work fine.
I consider posting a model here virtually equal to placing it in the public domain.
Use any model that I post that you like for what ever purpose you like.
If you want to protect your model from others my advice is don't post it.
If I post work from someone else I will credit their work.
Starting out building models can be overwhelming ,but running an existing model is relatively easy
Just copy the "code" for the model paste into a text file and rename or save as XXXXX.nec move it to the models folder of 4nec2 and open it with 4nec2 (the little folder icon on the left).
Click the calculator icon or hit F-7 and pick far field pattern and then Generate.
At first I learned more from tinkering with other peoples models than anything else .
It's also nice to have a template that when you feel ready you can just paste in the wires ect. and not worry if you forgot a critical line or got them out of order.
I was going to just post free space models but it's easy enough to change to any ground desired.
By convention one always starts with the simple antenna first, a dipole perhaps?
No, I think I'll come back to dipoles later there are examples included in the stock models included at install.
I think I'll honor hommers efforts here and use his build of a moxon made from an old walker as the first model posted here. It is also scratch built with variables in mind and pretty easy to dissect and follow.
Model 1
Code:
CM CB (11 meter) Moxon from Hommer BBs build/measurements.
CM AGT=1.006 (0.02 dB).
CM y is half the width of the antenna
CM a is the reflector end length
CM b is radiator end length
CM g is for gap
CE
SY a=29.5
SY b=20.75
SY y=77.5
SY g=5.5
GW 1 9 0 -y 0 0 y 0 0.375
GW 2 3 0 y 0 a y 0 0.375
GW 3 3 a+g y 0 a+g+b y 0 0.375
GW 4 9 a+g+b y 0 a+g+b -y 0 0.375
GW 5 3 0 -y 0 a -y 0 0.375
GW 6 3 a+g -y 0 a+g+b -y 0 0.375
GS 0 0 0.0254
GE 0
GN -1
EK
EX 0 4 5 0 1 0 0
FR 0 0 0 0 27.18 0
ENSame Moxon above moderate real ground.
Code:
CM CB (11 meter) Moxon dimensions from Homer BB
CM Model by GHz24
CM AGT=1.01 (0.02 dB).
CE
SY a=29.5
SY b=20.75
SY y=77.5
SY g=5.5
SY agl=240
GW 1 9 0 -y 0+agl 0 y 0+agl 0.375
GW 2 3 0 y 0+agl a y 0+agl 0.375
GW 3 3 a+g y 0+agl a+g+b y 0+agl 0.375
GW 4 9 a+g+b y 0+agl a+g+b -y 0+agl 0.375
GW 5 3 0 -y 0+agl a -y 0+agl 0.375
GW 6 3 a+g -y 0+agl a+g+b -y 0+agl 0.375
GS 0 0 0.0254
GE 1
GN 2 0 0 0 4 0.003
EK
EX 0 4 5 0 1 0 0
FR 0 0 0 0 27.18 0
ENMany of my models are designed or modified to show the answer to some question (or try).
How far apart should I stack moxons ? Should I bother if I can only go up ?? feet?
What if I delay the feed to one of the antennas?
What about a staggered stack?
I never got this model to show the qualities it should be capable of. (great f/b ratio)
maybe I didn't try the right combination of stager and delay.
If any one finds a nice version of this post the SY values needed to change.
Wasn't real happy with the stacks I don't think it's worth the trouble .
Code:
CM CB Moxon stack from Homer BB s dimensions
CM Model by GHz24
CM AGT=1.0 (0.02 dB).
CE
SY a=29.5 'reflector end length in inches
SY b=20.75 'driven element end length in inches
SY y=77.5 'Half the length of the antenna in inches
SY g=5.5 'Gap between reflector end and Driven element end in inches
SY sep=295.75 'separation between upper and lower elements in inches
SY u=0 'Phase lag for upper element in degrees
SY L=-0 'Phase lag for lower element in degrees
SY s=0 'Stagger in inches (upper element)
SY agl=120 'Height of lower element above ground
GW 1 9 0 -y 0+agl 0 y 0+agl 0.375
GW 2 3 0 y 0+agl a y 0+agl 0.375
GW 3 3 a+g y 0+agl a+g+b y 0+agl 0.375
GW 4 9 a+g+b y 0+agl a+g+b -y 0+agl 0.375
GW 5 3 0 -y 0+agl a -y 0+agl 0.375
GW 6 3 a+g -y 0+agl a+g+b -y 0+agl 0.375
GW 11 9 0+s -y 0+sep+agl 0+s y 0+sep+agl 0.375
GW 12 3 0+s y 0+sep+agl a+s y 0+sep+agl 0.375
GW 13 3 a+g+s y 0+sep+agl a+g+b+s y 0+sep+agl 0.375
GW 14 9 a+g+b+s y 0+sep+agl a+g+b+s -y 0+sep+agl 0.375
GW 15 3 0+s -y 0+sep+agl a+s -y 0+sep+agl 0.375
GW 16 3 a+g+s -y 0+sep+agl a+g+b+s -y 0+sep+agl 0.375
GS 0 0 0.0254
GE 1
GN 2 0 0 0 4 0.003
EK
EX 0 4 5 0 cos(L) sin(L) 0
EX 0 14 5 0 cos(u) sin(u) 0
FR 0 0 0 0 27.18 0
ENNotice the first GW line
GW 1 9 0 -y 0+agl 0 y 0+agl 0.375
has the Z coordinates (both ends) of 0+agl obviously the zero is redundant it's a remnant of rapid modification with the new nec editor. I'll address that soon. I should have removed them but I didn't want to chance garbling the model, and they still work fine.
