Today I unpacked the Leica R3 MOT ELECTRONIC that @miha sent me some time ago for an attempt to repair.
After practicing on a well-worn R3 MOT for the last few days, I felt sufficiently prepared to get to work.
See the story here describing all the technical details and guesses where the error, a jumping metering needle in the viewfinder, may be:
www.photrio.com
Miha reported that the metering needle in the viewfinder was jumping around in aperture priority mode.
So I checked the camera for functionality.
Result:
Contact problems
Unboxing
Cleaning all battery contacts thorougly with electronics cleaner including the metal screw-in battery holder that connects the batteries to ground.
Some dirt has come off.
The two LR44 batteries that were in the camera and which I cleaned too should still have sufficient voltage even under load.
The 3 volt battery shows a little more open circuit voltage, but there should be more volts. So it's no longer completely fresh.
The aperture simulator ring which couples to the aperture on the lens and transmits the set aperture to the camera's electronic measuring mechanism.
The transmission takes place with a cable pull. Here I had problems with my practice camera because the cable slipped out of its guide when I played with the ring.
The ring on Miha’s R3 MOT doesn't run smoothly, so I just turn it carefully against its spring with the Spudger so that the cable doesn't jump out of the guide. But with a lens attached, the rotation of the aperture ring occurs more slowly and in stages.
Cleaning would therefore make sense, but this would require the camera to be deeply disassembled.
The manual shutter speeds are plausible.
Selective and integral exposure metering, a Leica specialty, work.
The battery check light on Miha's R3 MOT stays dark when I press the small button with the triangle.
Anyway the lamp works on my practice R3 MOT.
So I'll swap the lamps later, assuming the lamp on Miha's camera is broken.
After practicing on a well-worn R3 MOT for the last few days, I felt sufficiently prepared to get to work.
See the story here describing all the technical details and guesses where the error, a jumping metering needle in the viewfinder, may be:
Leica R3 MOT ELECTRONIC: Heading into the unknown
Our colleague @miha asked me if I would like to look at his R3 MOT. There is a problem with a jumping needle in the viewfinder. Maybe also the aperture priority mode is concerned. I was hesitant about whether I wanted to do this. Because I didn't have a Leica R on the table yet. And although...
www.photrio.com
Miha reported that the metering needle in the viewfinder was jumping around in aperture priority mode.
So I checked the camera for functionality.
Result:
- Jumping needle in aperture priority mode confirmed.
- Shutter-speed times in aperture priority mode irregularily longer than indicated, errors often at 1/4 s indicated.
- All manual times plausible.
- When measuring selectively, the needle goes down when the trigger is activated.
- The battery check light on the side of the camera does not work.
- No change in status after I replaced the two LR44 batteries (1.5 volts) with a fresh 3 volt lithium battery.
Contact problems
Unboxing
Cleaning all battery contacts thorougly with electronics cleaner including the metal screw-in battery holder that connects the batteries to ground.
Some dirt has come off.
The two LR44 batteries that were in the camera and which I cleaned too should still have sufficient voltage even under load.
The 3 volt battery shows a little more open circuit voltage, but there should be more volts. So it's no longer completely fresh.
The aperture simulator ring which couples to the aperture on the lens and transmits the set aperture to the camera's electronic measuring mechanism.
The transmission takes place with a cable pull. Here I had problems with my practice camera because the cable slipped out of its guide when I played with the ring.
The ring on Miha’s R3 MOT doesn't run smoothly, so I just turn it carefully against its spring with the Spudger so that the cable doesn't jump out of the guide. But with a lens attached, the rotation of the aperture ring occurs more slowly and in stages.
Cleaning would therefore make sense, but this would require the camera to be deeply disassembled.
The manual shutter speeds are plausible.
Selective and integral exposure metering, a Leica specialty, work.
The battery check light on Miha's R3 MOT stays dark when I press the small button with the triangle.
Anyway the lamp works on my practice R3 MOT.
So I'll swap the lamps later, assuming the lamp on Miha's camera is broken.
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