[TowerTalk] Modeling multiband Yagi's

[Don W7WLL]

I asked Dan, AC6LA, offline if he had ever modeled the TH7DX, an antenna 
I've been using since it was introduced (repaired a few times) and for which 
I have a spare and a half. He said no but thought someone on Towertalk might 
have and suggested asking.

Anyone every modeled this antenna? Have any changes ever been suggested in 
the ham community that might lead to  improvement in structure or operation) 
If either of the latter are available, I bet TH7 owners in general would be 
interested in what what the modeling showed or what the suggested changes 
were.

A quick comparison I made from the old original HyGain manual that came with 
mine many decades ago vs the new manual available at the HyGain/MFJ site 
didn't reveal any differences, but I could have missed something.

Was told by a MFJ tech not long ago that the TH7 R 15 M traps (different 
PN's from those in the DE's) are built to measure out 100 kHz higher (?) 
than the 15 M DE's. Have  not thought this through yet.

don W7WLL