Nizo S800 lightmeter not working in auto

[DonFito]

Hello all,

Got a Nizo S800 with a temperamental light meter. In auto the meter does not work at all. When doing the meter test, sometimes the needle moves (to f8) sometimes it doesn't move at all. When moving the dial to manual, most of the time the needle will move, but sometimes it won't. The needle always move when doing a main battery test, and if I press the meter black button while doing the main battery test the needle retracts back to the right of f1.8.

Any ideas and suggestions as to how to repair the meter are very much appreciated.

I've put in:
- 2 new Wein cells (checked them with voltmeter, both are good)
- new AA batteries. Camera runs fine at all speeds (after following AJ's method to correct the sticky trigger)

For those that would like to open up their S800 but never have I've posted pics here, along with an electrical wiring diagram:

http://www.flickr.com/photos/48387069@N ... 749892432/

[bolextech]

One of the possible causes of your problem could be an intermittent contact cause by the meter battery check switch. As you know, this switch is activated when you depress the little black button in the center of the auto-manual pot. The switch contacts themselves are located behind the circuit board. The way it is designed, when the switch is depressed, it interrupts normal AUTO-MANUAL meter operation and the meter will then deflect to a position determined by the strength of meter's batteries. When it is let go, the meter returns to regular AUTO-MANUAL operation. The contact could be just dirty or sometimes the springiness of the contacts weakens and they fail to return properly. Check the condition of this switch and clean if necessary. If this doesn't solve your problem, there is another bad contact somewhere. In a worse case scenario, the faulty contact is the galvanometrer unit itself, which is very difficult if not impossible to repair.

Cheers,
Jean-Louis

[bolextech]

I just reread your post and have this to add:

There is no point in depressing both battery test buttons at the same time.
It is normal when doing so that the needle should stay at f/1.8.

Also, can you make the meter go through the whole range in manual or does it stop at some middle position?

Cheers,
Jean-Louis

[DonFito]

Many thanks for your helpful tips Jean-Louis.

I can indeed move the needle manually through the entire range. However, sometimes the meter works manually, other times it does not, it's totally erratic at this time. I'm sure the camera hasn't been used in a very long time, I cleaned and repaired the battery compartment, cleaned the contacts, and had to do the Time Lapse trick AJ recommends in order to get the trigger to release correctly.

As soon as I get a chance I'll open it up again and look at that meter switch.