Amperex PQ 6922 vs Amperex PQ 7308

Dogpile, if you read Ed_sawyer's post above my last post he writes about a third 7308 tube with a shield and no PQ. I am familiar with the PQ label in the heart shaped shield. I'm intrigued by the 7308 with shield and no PQ.

IMNSHO PQ=shield, it's the graphic that is on the tube. Sorry if I wasnt' clear. I have only had PQ with shield logo, not any that are either/or.

generally 7308s are quieter and better matched. they are selected 6922s, essentially.

the consumer versions pre-date the military versions in general. Age is by color of printing to a degree. white, orange, green for printing colors, oldest to newest. usually they have date codes on them too.

as with most tubes earlier=better.

-Ed

Thanks, Ed. That was my thinking, too. Therefore, I am assuming when Joe's Tube Lore is talking about Amperex 7308 with shield, he is discussing PQ tubes whether or not he specifically mentions PQ.

Ed, if 7308 are selected 6922, then what was does the PQ designation on 6922 tubes signify?

TVAD,

To answer your question, only the PQ version had the shield logo. The other one has the green JAN label.

Nhtran, thank you! I've been going nuts trying to figure out the different tubes and colors and labeling.