[Milsurplus] VT-191 for Homebrew?

[antqradio at sbcglobal.net]

Really Dave?  The tube making art is so shoddy that well over half of the tubes produced go to gas?  This doesn't square with my experience.  
I just finished testing several large boxes of used tubes and found that only about 10% didn't meet minimum performance or were special purpose TV tubes like HV rectifiers or damper diodes.  Only about 1% of those tested were outright dead.  Didn't see any difference due to age as big pin, octal, 7, and 9 pine tubes didn't appear to fail in larger numbers then any other.  Didn't bother to test compactrons since they are, for the most part, special purpose TV tubes.
I think the Tube Collector's Association has well over 400 members and perhaps there are several times that in tube collectors who are not members so I hope that the McDonalds are much larger in Texas!Regards,Jim
      From: David Stinson <arc5 at ix.netcom.com>
 To: milsurplus at mailman.qth.net 
 Sent: Thursday, March 9, 2017 6:26 AM
 Subject: [Milsurplus] VT-191 for Homebrew?
   
While it's a cool-looking tube and all (UFO!),
I'd hesitate to build a transmitter for it.
The majority of those tubes have gone gassy.
I've seen many NOS in the box and exactly
*two* that still had intact seals.  I'd suspect that
once a "good" one was placed in service with 
all the heat it generates, the flawed pin seals 
will let go on them as well.

But then- it's not like we're talking about the 
Mona Lisa here.  If you gathered every person 
who still cares about preserving these tubes in 
the entire world to lunch, you probably could
get them all in the local McDonalds.  So maybe
it would be worthwhile just for your personal 
joy and satisfaction.  If not used for something 
like this, their inevitable fate is to sit in a box
until their trip to the landfill.
One man's opinion....
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