In message , RST Engineering
writes
I tried simulating a Slim Jim in EZNEC and did NOT get the expected "aim at
the horizon" low-angle radiation simulated pattern. I got instead the
standard "hole in the donut" that you would expect from a vertical dipole
and a rather fat true donut shape rather than the expected pancake pattern.

I'm not at all sure how to connect a "voltage source" driver at the tap
point without being able to simulate the ground of that voltage source
tapped up from the bottom end as well.

You should have a wire across the bottom of the antenna at the tap
point. The voltage source is in the centre of this wire. A real Slim Jim
would be fed with a balun so both halves of the matching section are fed
symmetrically.

This however won't change the radiation pattern. There's nothing magic
about a slim jim, it's just a voltage fed folded dipole so the radiation
pattern will look like a dipole.

73 Brian GM4DIJ
--
Brian Howie