Strange 6C33C tube symbol
Here is a 6C33C-B vacuum tube, a tube which is found in, say, Lamm ML1.1 and ML2.1 amplifiers.
In trying to accurately identify this tube, one might reasonably try and describe all information printed on it to somebody, say, over the phone.
This particular tube then, is the “6C33C-B ‘phallic symbol’ 81 with an OTX 7 in a diamond” tube.
At least, that is what I overheard people talking and laughing and wondering about as I was, as usual, hard at work in my office. 
[OK, Neli wants me to remind everybody that there is something on both sides of the phallic symbol….
On the left is the month and on the right is the year of manufacture.
Me? I’m calling it a ‘rocket ship’].
February 3rd, 2008 at 7:26 am
come on … It is known that is code symbol of the manucturer (standard in Soviet time). In this case that is Ulyanovsk plant.
February 5th, 2008 at 10:18 am
Hi Nikolai,
Yes, but for the average person who has not yet passed the Tube Manufacturer Code Symbol Recognition Tests yet, we have to refer to it in some manner that provides minimal embarrassment for all the parties involved.
Or maximum embarrassment, depending on just who they are, the slackers…
Seriously, it is all just in fun. A little humor for this hobby that takes itself WAY too seriously most of the time.
Thanks,
-Mike