Repair help for Hitachi V-212 scope

[TexasTwister]

Howdy,
I am new to this message board and recently purchased an Hitachi V-212 scope off eBay along with a curve tracer to fix arcade video boards I also purchased off eBay for my own personal use. Anyway it appears CH1 X input is not functioning as the adjustments knobs don't adjust but CH2 Y works okay so it is worthless with the curve tracer so I have downloaded the service manual but thought I would ask what is the best starting point before I open up the scope.

Thanks so much,

TexasTwister

 

[D.A.(Tony)Stewart]

You probably want to replace all power electrolytic caps as they will be near end of life and start with a visual inspection.
A capacitance meter that reads ESR would be helpful.

Then start debugging by comparing channel quiescent voltages.