Who told you PVC was lossless? Stick a sample of it in a (2.4 GHz) microwave oven and see what happens. You could
simulate it with a sheet of carbon impregnated foam, but I guess 4nec2 doesn't handle that either. If you need a
radome, use foam polystyrene, commonly known as Styrofoam®.

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Crazy George
Remove N O and S P A M imbedded in return address
"Alex" wrote in message ...
I have successfully constructed various 2400 Mhz antennas using the
4nec2 antenna modelling software (really great application, warm tnx
to the author should he read this!)

What I would like now is to get a rough idea as to how close I can put
the antenna elements to a PVC casing without disturbing the radiation
pattern, SWR etc.

E.g. by putting a 2 mm lossless PVC sheet (with dielectricity constant
= 7) 1 cm in front of the antenna element.

Is it possible to simulate this?

Alex