Can someone suggest an LRC circuit to produce a Smith Chart similar to this? Red marker is at 3.7 MHz, and the blue one at 4.0 MHz. This is an actual antenna and I am trying to improve the match to 50 ohms over the 3.7 to 4.0 MHz frequency range. Figured I'd need to start with an equivalent LRC for use in a sim.

Years ago when I was still working I had access to an old version of Touchstone, in which I could enter the .s1p file directly. Really miss that program. Don't think I can input a .s1p to LTSpice or Elsie.

Years ago when I was still working I had access to an old version of Touchstone, in which I could enter the .s1p file directly. Really miss that program. Don't think I can input a .s1p to LTSpice or Elsie.