[TowerTalk] Need specs for 15m helical hairpin match on Force 12 C-31XR / C-51XR

[Scott Dickson, W5WZ]

I am assembling my C-31XR / C-51XR stack with a separate feed line on each
band.  The F12 manual indicates the need for a helical hairpin match at the
15m feed point, and makes reference to reducing the number of turns to 3 if
wide spacing is required to get a good match.

What is missing, however, is the diameter of the hairpin coil.  If anyone
can help with that, it will sure help.

--Scott, W5WZ

See my station building progress at W5WZ.com