Leica METER MR Troubleshooting

[Trutta]

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I just got one, does anyone out here use one?  I loaded it up with a 1.3 Wein cell. I was curious that when the battery test switch is depressed the needle shoots all they way down past the silver dot to the bottom of the window . When the needle release knob is depressed to measure the light it reads accurately for both inside and outside when measured side by side with another light meter.  Does the needle have to rest on the silver dot? 

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[onelensman]

I have a MR4 meter that exhibits the same behaviour, ie meter needle swings well past the test mark when the battery test switch is pushed. It should stop at or near the silver dot. I have opened the meter a number of times to clean the circuit board tracks and switch contacts. There are two resistors in the circuit, one is visible on top of the board which controls the current to the light measuring switch and a second resistor which controls the current to the battery check switch. The latter I have yet to locate and may be soldered under the circuit board. My guess is that there is a short circuit across this resistor either due to corrosion or component failure. I will at some stage need to to do a full disassembly to address the problem

[plaidshirts]

On 11/8/2023 at 11:01 AM, Trutta said:

I just got one, does anyone out here use one?  I loaded it up with a 1.3 Wein cell. I was curious that when the battery test switch is depressed the needle shoots all they way down past the silver dot to the bottom of the window . When the needle release knob is depressed to measure the light it reads accurately for both inside and outside when measured side by side with another light meter.  Does the needle have to rest on the silver dot? 

It’s supposed to according to the user’s manual. Mine, even after a CLA by DAG, doesn’t either. I wouldn’t worry about it if your measurements are correct.