How to design a matching network using shunt with NEC ?

[rfc]

NEC design problem

Is there any way to design a matching network using shunt elements with an nec based program? It appear that only series loads are allowed. I need a shunt negative reactance to ground at the feed point. I'm using eznec.

rfc

 

[flatulent]

do you really need it in NEC

Do you really need to combine the impedance matching function with the other things you are calculating with NEC?

You can get a tablulated impedance values and then put them into a spread sheet and do your matching there. Just compute Y of the antenna input and then add your reactance and then invert the new Y to Z.

 

[rfc]

The way I do it is to fine the feed point impedance, then match with a smith chart. I would like to simulate the smith chart answer using NEC to verify the result. Guess I can't!

rfc

 

[flatulent]

zmatch

Here is a link to an impedance matching program https://www.zzmatch.com/ It will work for free for 20 days.

 

[rfc]

Actually you can design the match with an open stub then work backwards with a smith chart to determine capacitance. Just tried it out and it seem to work.

rfc

 

[egliu]

Re

you should separate antenna and match networks, Using Nec, get antenna impedance firstly and design networks using any type smith chart software