From: pfjw@aol.com   
      
   On Thursday, October 16, 2014 4:25:39 AM UTC-4, Patrick Turner wrote:   
      
   Much snippage   
      
   >    
   > I was given maybe 4 tube testers over the 20 years after 1993 when I decided   
   to become as near an expert as I could with audio amps and radios using tubes.   
      
   > I never came across a tester from 1960s which may have actually survived the   
   technicians who used it. In theory, if any tube has an internal short circuit   
   then it should not hurt the tester if you plug it in with correct switch   
   settings.   
   >    
      
   > I also have a few ancient tubed oscilloscopes, and some dismantled vacuum   
   tube voltmeters. All are complete junk compared to much stuff I have acquired   
   which was made after 1980, with not a vacuum tube to be seen.   
      
   I keep two testers - a diddly-simple Simpson emissions-tester that also   
   handles shorts and gas that fits 99-44/100ths of the need, and a very nice,   
   well-kept, properly calibrated Hickok 539B late of the GE Re-Entry Systems   
   Division in Philadelphia before    
   it closed down these many years ago. Both have been out-of-case cleaned and   
   calibrated (in the case of the Simpson, to the extent it can be) and both do   
   nicely.    
      
   At the same time, the only valid test of any vacuum tube is its circuit. A   
   tester is not much more than a go/no-go device in most cases.    
      
   Getting to that 66/100ths use(s): Matching. Some few circuits prefer   
   reasonably matched tubes at least initially. And very, very few testers are   
   capable of actually matching. The Hickok 539 series (A,B,C) can match - albeit   
   with one or two additional    
   outboard VOMs attached.    
      
   And, of course, the big honking tester with three meters and enough switches   
   to be massively confusing does impress the impressionable.    
      
   I do have all the update pages (through 1990 anyway) for both testers, so   
   there are few tubes that are not listed. And I have acquired WE test data for   
   the Hickok - as they made the WE testers under license.    
      
   But with all of that, and all the equipment that passes through my hands the   
   either tester seldom sees the light more than 3 or 4 times per year outside   
   Kutztown, where the 539 is in heavy demand by the tube vultures - the club   
   performs free tests at the    
   Clinic table.    
      
   Peter Wieck   
   Melrose Park, PA   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)