View Single Post
  #5   Report Post  
Old March 1st 13, 04:43 PM posted to sci.electronics.design,rec.radio.amateur.antenna,rec.radio.amateur.homebrew
legg legg is offline
external usenet poster
 
First recorded activity by RadioBanter: Oct 2006
Posts: 8
Default Antenna Simulation in LTspice

On Wed, 27 Feb 2013 22:07:51 -0500, rickman wrote:

snip
There is a resonance near the frequency I would expect, but it is not so
close actually. I can't figure why it is about 5% off. There is a
second resonance fairly high up that I can't figure at all. None of the
component values seem to combine appropriately to produce this peak.

snip

Pulling out the old reactance paper, there are a couple of expected
interactions using the values present:

Around 50KHz (89.42uH+48uH) with 50.42nF (L3+L1) with C1
Around 290KHz (89.42uH+48uH) with 6.25nF (L3+L1) with C2*N^2
Around 360KHz 48uH with 6.25nF L1 with C2*N^2
nL1/nL2=N=25

The mid-resonance is a dip or rejection.

What's the issue?

RL