[NLRS] 50Mhz antenna modeling question

[Matt Burt]

I have built a few antennas for six and now feel the need for something small
enough for the rover and yet capable of a little forward gain.
The last three roves my delicate 6M moxon has been damaged due to a mis-hap with
a tree on my route (one tree is 6 blocks down the road on the only road that
leaves the subdivision).  As always I will try to get my antenna up as high as
possible ... but not much more than 20 ft is very practical. Of course I have
used 3 or even a four element at 15-18ft and had good luck. 

Any way armed with an old DOS program for calculating dimensions I came up with
a 2 ele 50Mhz antenna of the following specs:
REF 117.3"
DIR (DRV) 116.53"
BOOM: 30.7"
expected forward gain 4.74 dBd
F/B not very good
element size .375" (maybe .50" at center)
My plan is to feed the driven element with a T match and 1/2W length piece of
coax tuned for 50.140.
The "Z" looks like 49 ohms with some inductive component
Any modelers out there that can duplicate my numbers?

KF0Q