CdS meter repair / diode fix for Mercury battery replacement

An article dealing with the calibration and repair of a Gossen Lunasix 3 (LunaPro) meter, but also applies to many CdS meters, and using a diode to modify circuits so they can accept non-Mercury batteries as a voltage/amperage equivalent power source.

Article: www.biasedlogic.com/index.php/calibrating-gossen-lunasix-3-lunapro/

Additional CdS meter info: www.biasedlogic.com/index.php/on-cds-meters/