Yeah, there seems to be a trick to that, as his files are .ez not .nec. What I do is download his files, right click and choose open with. Then browse to the 4nec2x.exe program. It opens the file with warnings, but they work anyway and are converted to nec files. Ive also downloaded and installed the files for additional segments up to 10,000 (I think, I have run a 5600 segment (xg91) far field pattern so far).Anyone know where I can find a model for the above antenna, tried KQ6QV, its there but have error on my attempt to use the file for the cm-4221, segment errors.