gerald_steinbach1

Try a fresh battery. With copletely black negatives it looks like a problem with the shutter, since this is a electromagnetic device in Minox, battery seems to be the most likely.

Can't be the Battery as long as they are relatively fresh and not completely down. The circuit works as an comarator, and was specialy designed to work with a power supply with variable tension. Meter reading is almost not affected be battery tension. Since the movement of the needle uses to little power (high resitive) to show a drop in battery-power the Battery test uses the same circuit as the meter whith an resistor to simulate a low resistive power"consumer". Metering circuit is high resitive. What is affected and where the problems arise is the shutter, which is electromagnetic and low resistive. Meter reading is approximative, don't compare to a hand held meter or any other "exact" meter as long as the difference is not completely of. Sometimes it helps to clean the meter window.