LOT : MATCHED QUAD GRADE "1" OF 6N2P-EV "SILVER" BOXED ANODE TRIPLE MICA
(6Н2П-ЕВ "Серебряная" тройная сетка)
TUBES tested with L1-3 tester
All tubes are new (NOS NIB), from the same batch.
Produced BEFORE 1973 year (old version), extra rare type.
MATCHING GRADE "1": "Excellent" tubes - the difference between their own parameters is not more than 1%. - THIS LOT
IMPORTANT NOTICE!!
You can get differ tubes with other parameters, not like at the photo.
Because I have many tubes and can not make photo of each.
So, you will get one Matched QUAD with very similar parameters (WITH 1% tolerance),
but they must not be the same as at the photo.
TESTING PROCESS INFO
We actually test all sold tubes on L3-3 testers (sometimes L1-3).
We have more than 10 such devices each ajusted precisely for the specific tasks.
When selecting tubes close in parameter, we re-test on the best (carefully calibrated devices.
It is theoretically impossible to select tubes with a difference of 0% on any device.
From a batch of 100 pieces of any new or vintage number of pairs with a spread of 1-2%, no more than 10.
During testing, any tube changes its parameters by 1-2% in any direction over time.
This information is based on inspections of over 100,000 tubes over many years.
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