Inmel / Lumel SQ10 Calibrator: Searching schematic or service manual

[richipedia]

Hello everybody,

I've got this beautiful Inmel SQ10 calibrator lying around.

Unfortunately, the 100 V and 1000 V ranges are not working, and the other ranges seem to be a little out of calibration.
Can anybody provide me with a service manual, or in particular a schematic or a calibration procedure?

[Robert999]

Dzień dobry , mam pytanie czy udało się Panu naprawić kalibrator sq10 ?
Pozdrawiam