Does a B&K 747 test different tubes than a 747B?

[smoker76]

I checked other sites and found a report that it has a couple function upgrades that are somewhat insignificant.

Do tubes for things like TV cameras, station equipment, old computers have unusual tube #'s?
I am amazed at how many variations of every single thing there are. I am surprised there are enough people to do all the behind the scenes work.