Here is what it does from the sales brochure.
Providing facilities for testing all five important
engine areas, the 820 includes the Sun Scope,
Voltmeter, Ohmmeter, Dwell meter, Tachometer,
Condenser and Coil Testers, Combustion Effi-
ciency Tester, Vacuum Gauge, Cylinder Leakage
Tester, Timing Advance Control and Cylinder
Balance Tester. All of this top quality instru-
mentation combined in the most complete tester
ever available.
All new, Electronic Ignition Scope with easy-eye,
edge illuminated screen, provides over 36
square inches of viewing surface. Displays sec-
ondary and primary ignition patterns inde-
pendently or simultaneously with just the flick
of a switch. Newly developed, special cathode
ray tube, displays each portion of the ignition
pattern brightly and distinctly. Makes analyzing
all types of ignition problems a breeze. Equipped
with a universal pattern pickup, compatible to
all existing ignition systems.