I have a ceramic capacitor which comes from a circuit board from the late 70's-early 80's.
The schematic diagram from the manual says it's 680pF.
The markings on the cap says 680 SMZ.
Back then, did they use different code markings than what they use today?
A cap with those 3 digits today would be a 68pF cap, would it not?
I tried testing it with my DMM it capacitance mode and got 2.21nF and climbing.

 

Back then, did they use different code markings than what they use today?

Reading small caps has always been a headache. Which corporation? Which marking method?
You would think if they meant 68 and no zero's, they would just mark it 68.

I say, believe the schematic. Go with what the designer meant and refuse to guess what the capacitor manufacturer meant.
As for your meter? It is reading nothing similar to the expectation. Doubt your meter.

 

Thanks. You were correct on all counts. The schematic was correct.
Changed the batteries in my DMM and the cap reads 0.67nF (680pF).