[TenTec] 75 Ohm twin velocity factor ?

[Steve Hunt]

Jerry,

Despite using the wrong formula I guess I came to the right conclusion .... you can't get down to 75 Ohms without some "non-air" dielectric.

I have three HP41C calculators (one in the house, one in the shack, and a spare) and was surprised something so sophisticated doesn't have hyperbolic functions; but I believe they were available on one of the plug-in math modules.

73,
Steve
  ----- Original Message ----- 
  From: Dr. Gerald N. Johnson 
  To: tentec at contesting.com 
  Sent: Friday, January 26, 2007 11:43 PM
  Subject: Re: [TenTec] 75 Ohm twin velocity factor ?


  My HP-15C that I keep in the drawer between this keyboard and monitor
  does have arccosh. I used to keep XACT on my packet computer, it
  emulates an HP11, I think. Runs in DOS. The scientific mode calculator
  that came with Fedora Core 3 gets the same answer of 158.0349 ohms Zo
  for 1/2" conductors, with 1" center to center spacing.