Re: Weak 9872CT Plotter Platen
The reference being slightly higher would only mean the high voltage would be a bit higher. The fact that you see 5.2 volts at the - input of U102 would suggest that there is high voltage since it is fed by a voltage divider with approximately 90 to 1 ratio . What do you get at the cathode of CR103? What sort of a meter are you using? If it is a digital meter they usually have an input impedance of 10M especially on the higher voltage ranges.
On 2020-01-22 6:53 a.m., Martin Hepperle wrote:
Thank you all for your comments and hints. I guess my test equipment is not perfect for these tests and now I am not sure that the platen itself is the problem.