Vacuum Tube Testing Services?

Yourself!

https://www.ebay.com/itm/133738676352?hash=item1f23724080%3Ag%3AzsQAAOSwvB1ggtLP&LH_BIN=1

I have a big fancy Hickock, and the earlier Accurate Instrument 157.
The little portable 157 has never been wrong. I'd like to have this 257.

I highly recommend everyone with tube equipment to get a simple tester. You live with Tube Confidence!

I check: what I buy; what I am using periodically; what I pull from stock from all the tubes I have been given/acquired.

Used tubes: many tubes last 10,000 hours. I had a friend who gave me bags and bags of used tubes pulled from TV's, etc on the way to the dump. I had a client bring me a gigantic Samsonite suitcase full of tubes he had in his mother's basement, from Chicago to NYC. People's parents die, they give me their father's tube collection. I see a bargain at a yard sale. Point is, the great majority of them are good. Without a tester, you would have no idea.

I just had Audio Classics overhaul my mx110z tube tuner/preamp. I had filled it with vintage tubes (17) I tested on my 'toy' 157. You would expect them to sell me some new tubes. Nope: Ryan said, "they all tested good on their tester, you can't beat those vintage tubes". It came back with new gold-plated rca jacks, what a wonderful thing. 

Make sure you get the manual, some have supplement books 

This one restored, recalibrated

https://www.ebay.com/itm/324626522534?hash=item4b953fa1a6%3Ag%3AwGEAAOSwly1goJvG&LH_BIN=1

Thanks for the suggestions but I am looking to get Gm and Ma results to ensure my output tubes are closely matched and how strong my preamp tubes are performing.  These testers appear to really just test to see if tubes are good or not.   I have approx 15 tubes I needed tested to use or sell and prefer not to buy a tester at this time.

Found a service that sounds promising.  Will give it a go…

https://www.western-glow.com/vaccum-tube-testing-matching/

When I was in high school, I worked in grocery store. We had a tube tester

with a tube cabinet. Back in those dark ages, many stores of all kinds had tube tester cabinets. When the TV went on the fritz, people would pull all the tubes and put them in a sack to bring to the store to tst and replace as needed.