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Strange how many used valves measure NOS?

Finally fired up my valve tester.
All I can say is be very afraid.
Out of boxes & boxes of used valves bought on here
and ePain, most of them are crap.
I don't mind the odd chance buy being duff but some bought from here cost a fair amount and I'll be taking "measures as NOS" with the pinch of salt it deserves on ebay from now on.
There's either a lot of uncalibrated valve testers out there
or a lot of lying b------s.
I think it may be the case that some of these have been tested many moons ago by the original owners, marked up then used for a few years then the resellers think since it's marked 90/90,
it's still nos.
Bizarre, I have definite NOS 6SN7's that struggle to make 90/90.
Still it's fun to discover the occasional diamond amongst the rough.
Yes I will be getting the tester's calibration checked but having done dozens of valves and half a dozen different types, I can't see that it can be far out.
We live & learn.
simon74
rocketman4274
21 posts
 
I have out the hard way,there are only a few honest tube sellers out their.Twio that come to mind are Jim Mcshane and Kevin Deal.There are a few others,Mcshane offers money back,deal test the hell out of the tubes and burns them in.There is only a few who test them like Kevin but you pay the price.
aball
2,016 posts
 
Maybe I have been lucky but many tubes I buy as "used" actually test like new. I have only once gotten a dud - a 6AB4 I bought on ebay. I disregard the NOS label until I test them myself.
mattybumpkin
590 posts
 
I recall reading (I think) that many tubes will test in the new range even though they are used. But at some point test wise they drop off the table (not a smooth curve between new and used). Don't hold me too it though.
simon74 OP
216 posts
 
Tested more today and the tester died - solid state here we come! Only joking.
Strangely some definitely nos tubes I have test mediocre but sound fine and some that test brilliant are noisy as hell in the amp.
Will have to sort and calibrate the tester as it's strangely addictive - like the lottery I suppose.
I must admit to having had :-(visons of sparks, smoke and spectacular explosions but it was good as gold whilst it worked.
Strangely enough there are still places here in the UK that sell good valves at reasonable prices, just a shame that I prefer US of A valves over the soupy examples of Brimars and Mullards I have tried.
If I ever manage to get my dream amps (lots), I'll be a paranoid wreck given the price of replacement tubes.
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