[TowerTalk] Vacuum tube 100 years old today

[Chuck O'Neal]

Love this thread!  I lurk here, but have to add this.  I took the last
vacuum tube course offered at my college, (Tufts) in 1969.  Yup, I'm an old
buzzard.  Still know how to design using load lines and optimize an AB1 or
AB2 linear the old fashioned way....if you can trust the curves.  Tubes
vary.  Years ago, in the engineering dept of the first company I worked for,
Varian, I was told that many tube manufacturers would supply "limit" tubes
that represented each end of the performance spectrum, just to be sure that
a circuit you designed would work over the variaton of tubes that you  may
see. I still have a tube tester, an old Hikock 539C that I use to check
tubes for some of the old boatanchor receivers I still use.  SX-28A,
NC-240D, HRO-60, SP-200, Drake R-4...ect...

73,
Chuck...K1KW