B&K 970 Transistor Tester

Just picked up a B&K 970 Transistor tester, very cheap from auction. Does anyone know much about these , imfo as far as manuals /schematics etc...?

Is this a piece thats worth looking into repairing if needed to have handy ?

I've had one of these around for a few years. It was given to me, and like the OP, I'd like to know more about how to use it. I think I have the transistor testing function figured out, but it looks like it has a radio tuner alignment function that I don't know how to use at all. Pictured here:

http://www.slack.com/images/TE/B+K970.jpg

Any assistance would be appreciated!