Used Tektronix Oscilloscope. Oscilloscopes display graphs of electrical signal. 
You could use this for a number of things. 
Determining time and voltage values of an electrical signal, caculating frequency of an oscillating signal, or viewing moving parts of a circuit is no problem. 
This oscilloscope is used, and in good condition. 
It powers on when plugged in. 
That is all the testing we have completed. It seems to be in working conidtion. 
Details are provided below. 
              
           Details:
Manufacturer: Tektronix 
Model Number: 7623 A 
Form Factor: Mainframe 
Bandwidth: 100 MHz 
Rise time: 3.5 ns 
Main time base - lowest 5 ns/div 
Display Type: CRT Monochrome 
Display Size: 13 cm 
Display modes: Bi-stable,Persistence 
Width: 221 mm (8.7 in) 
Height: 305 mm (12in) 
Length: 597 mm (23.5)