[dieseljeep]

Originally Posted by Electronic M

My tester has found plenty, but this is the first time a tube has actually boasted being sub-standard in text to me.

Strangely enough it tests and works fine. I got a good chuckle out of an RCA 6AC7 boasting it's shoddy quality...It was probably RCA's way of marking factory seconds, but I can't help finding it's wording/application about as funny as Motorola's "DO IT RIGHT" stickers.

That tube was made during WWII and had to be marked as such. It didn't quite pass JAN standards, for the Military.
THE MR meant "Maintenance and Repair" and could be sold to the public, as new radios weren't available during the war.
Some referred MR as being Military Reject, but the former is the true meaning.