Wadizzle,
I own and use several different Tektronix scopes and my least "green" one is a Type 555 true dual beam scope with dual plug in vertical channels and dual plug in time bases. The power supply sits on the bottom of the scopemobile cart and both are loaded with vacuum tubes and cooled by separate very large fans. In operation the 555 draws close to one kilowatt. It is still in perfect working order and like other 500 series lab scopes it is reliable and easy to maintain although adjusting the lumped constant delay line is a tedious process.
My primary bench scope is a pair of somewhat newer Tektronix 7854 scopes although I do also have a smaller but less capable new Tektronix LCD screen scope that is convenient but there are times when I need the versatility of the multiple plug-ins which provide so much versatility with the older models.
Nobody wrote better technical manuals that the folks in Beaverton and Tektronix documentation puts most other manuals to shame in terms of content, organization, and overall clarity. The construction quality of the older scopes was also a thing of beauty with their ceramic strips with silver contact points and in the interior photo of the 555 you can see the roll of special silver bearing solder that Tektronix shipped inside of each of their instruments. It was truly a world class organization from design through manufacturing and customer followup.
Rodger
