Joe...I use an Amplitrex AT1000. It a killer machine, well built and I love it. Does them all. Lots of sockets and adapters. Huge database.
http://amplitrex.com/
When I'm in the mood, I hook it up to a PC via its USB to graph and print results. The software user interface is a little clunky by today's standard but it works nicely.
A good tube tester is a must have if you have tube driven HiFi equipment. I generally test twice a year given that I have a hybrid 2-ch / Home Theatre setup. The HT side of things clocks the hours up on the MC2301s especially. The proof is in the hours and I have pushed the hours. The MC2301s + Genalex Gold Lion KT88 Re-issues (Russia) are a strong, solid and reliable combination.
Amplitrex AT1000 at work testing Gold Lion KT88 and Telefunken ECC801S tubes pulled from 3 x McIntosh MC2301 tube amplifiers. Weak tubes were replaced and quads were re-matched according to test results.
Sometimes when you get an unusually hot result on an ageing tube, it pays to perform another reheat and test with the autobias setting off. Although this tube tested strong on the first test at approx >8,000 hours, it was unstable and has since went super-nova.
Oh.... And the Amplitrex AT1000 lets you plug in headphones so that you can listen to the tubes to hear if they are noisy or microphonic.
It's nice to share the love. Lol. :kiss: