Some of my Test Gear.

[Shaman]

Hi schottky, i think your Telequipment D83, is more modern at it uses transistors more. The old 545 and 535 scopes had very limited use of transistors, what i can make out they were of poor quality, performance wise, so they were heavily valved, some of the plug ins have transistors, again not high performers, your scope is smaller, so it is easier to move around, the old Tek scopes were hernia makers, they were too heavy......Alan.