I've not seen this on the list but I have from a reliable source that 2 or 3
years ago the new production of 8122's are manufactured and sorted by gain
with red, blue, green, black etc. stickers put on the tube box. Burle did
this without any fanfare or notice to users and caused me some grief.
I can verify the stickers are on new boxes and I can verify that the gain
and worse the idle characteristics changed in 1997. This tube change
required modifying the screen supply in a Harris TV transmitter that I've
lived with for 20 years or so.
First, if you use 8122's from 1997 or later production in commercial or
amateur service you will want to know about this. Also, if someone on the
list has knowledge of which "color" most closely matches the original specs
I'd personally like to know.
Pat, WA4TUK
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