I don't think phillips or telefunken ever made 6an8.Just a better than RCA or GE tube. Don't see any older Mullards or Teles in this number.
I bet you're right, Art! I only have one of these, a 7189A that is a Mullard Blackburn re-label. Still good, so I haven't tried to turn it in for a replacement. Wait--they RadioShack is now defunct.....
Some GE 6AN8As were marked "Made in Gt Britain." I don't know who the OEM was - Mullard used "Made in Gt Britain" on tubes they made but there are no Philips codes on the glass. I can't tell you how they sound, since I'm using them in a Tektronix oscilloscope I'm reviving.
Hi Terry, is the 7687 a drop in replacement for the 7199 or does it require a rewire of the socket?There are two "premium" pentode - triode tubes I know of is the Sylvania 7687 and the European E80CF. The 7687 was supposed to be a 7199 killer and the E80CF was a uprated 6BL8. Both are plug & pray if you have a 6GH8 pinout.
The 6AN8 is a great sounding tube and there were JAN military out there too.