[AMPS] Re: Arcs

[w8jitom@postoffice.worldnet.att.net]

> >All the stuff you and Rich blame on "parasitics" is mostly arcs due 
> >to outgassing and seal leakage. ...
> 
> Funny thing that the alleged Rauchian gas disappears by the time that the 
> kaput tubes are removed from the amplifier and tested with a 
> high-potential tester. 

Not a funny thing at all, common sense. 

In the publication "Getters and their Function in Vacuum Tube 
Manufacture", arcs are listed in methods of gettering a tube.

Also, not all arcs are gas. Some are from what are referred  to as 
Barnacles, high spots on the grid or anode. An arcs usually removes 
Barnacles.

> I tested a pair of kaput 3-500Zs for Rod, W7OM, 
> this morning.  Both appeared to have been damaged by VHF parasitic 
> oscillations.  However, the vacuums tested good.  At least one of the two 
> appeared to have a bent filament--like the one on page 15 in the Sept. 
> 1990 *QST* article "Parasitics Revisited".  .

Like asking Dr. K if the patient needed to commit suicide, isn't it? 
;-)

73, Tom W8JI 

--
FAQ on WWW:               http://www.contesting.com/ampfaq.html
Submissions:              amps@contesting.com
Administrative requests:  amps-REQUEST@contesting.com
Problems:                 owner-amps@contesting.com
Search:                   http://www.contesting.com/km9p/search.htm