[AMPS] gettering

John T. M. Lyles jtml@lanl.gov
Thu, 13 Sep 2001 14:08:52 -0600


>//   Where is the getter in a 3-500Z?
>Where is the getter in an 8877?
>Can gettering take place while a tube is cold?

I recommend contacting the manufacturer for these questions. If you 
prefer to avoid Eimac, then talk to Claude Peterson at Econco in 
Woodland, CA. (800) 532 6626. He was involved with some of the glass 
Eimac tubes at Salt Lake City before they sold that operation. Maybe 
the 3CX1500A7/8877 as well....
Let us all know what you find out.

>//  What if an amplifier was generating energy above the HF passband of
>the tank, where the energy produced could not be dissipated in the load?
This would force voltage or current somewhere. Probably where it 
isn't wanted. I would think it more likely to happen in that case 
either at a harmonic resonance in a line circuit or at a resonance 
due to the inherent inductance and capacitance of components in LC 
tank which stack up (resonate I mean) at some other frequency. Its 
been covered in QST and ARRL and Orr and Terman for many years.

>//  However, such gas seems to vanish just before the suspect tube is
>affixed to a high-pot tester.

Hi Potting IS a cold process, no thermally driven electrons involved. 
Try hi potting a tube with bias and with the heater lit, and you may 
see otherwise. We hi pot cold often just for incoming test (for 
warranty purposes), then let the RF voltage or just plate voltage run 
with bias, etc, and the tube lit, to further process.

73
John
K5PRO

-- 

--
FAQ on WWW:               http://www.contesting.com/FAQ/amps
Submissions:              amps@contesting.com
Administrative requests:  amps-REQUEST@contesting.com
Problems:                 owner-amps@contesting.com