Please help! Lightmeter Nikkormat FT2

[p81]

Hi guys,
I need some help, because I didn’t find a solution yet...
So, the problem is the lightmeter of my FT2, it doesn’t react to any change of light.
To show you the problem, I added some pictures. First I centered the needle to get the actual light situation. If I take away the light with my hand, nothing happens... if I light into the camera with a strong lightsource, the needle reacts a little bit to the plus-side.
So, what could this be? Where could be the problem? Are the CdS-cells tired? Or the resistor in the lens coupling dead? I cleaned that out, without any change in the situation. Does anybody of you know a fix?
Any help is highly appreciated!
Thx in advance.

 

[p81]

Nobody any idea?

 

[Sirius Glass]

Call George Milton at Quality Light Metric to see if he can repair and calibrate it for you. 323 467 2265

 

[BradS]

Send it out to a competent professional repair technician. Sirius has mentioned one, there are many others.

 

[Alan Edward Klein]

I have an FT3 with similar problems. Intermittent. Someone once said it has to do with the resistor, maybe the slider potentiometer. I don't know how it's fixed. If you figure anything out, please post it here.

 

[p81]

Hoped, somebody had the same problem solved. I checked the potentiometer in the lensmount, it looks like new. But I‘ll measure it next time. The mistake has to be anywhere.
The lightmeter reacts to inputs at the aperture ring, so I think it has something to do with the light sensors...

 

[Alan Edward Klein]

This is what happens when things get old. They start breaking down and not working. Believe me. I know.

 

[Chan Tran]

Hoped, somebody had the same problem solved. I checked the potentiometer in the lensmount, it looks like new. But I‘ll measure it next time. The mistake has to be anywhere.
The lightmeter reacts to inputs at the aperture ring, so I think it has something to do with the light sensors...

whatever it is it's not the resistor because when you don't change any setting the resistor doesn't move and it should response to the light but you said it would response very little. It could be bad Cds cell but could be the power from the battery to the rest of the circuit.

 

[Alan Edward Klein]

It could be the potentiometer (pot) which is a variable resistor. A pot probe slides over a variable resistor to change the amount of the reading of current flowing in a linear and consistent way. If the slide wore out the pot where the probe meets the resistive portion, you could get erratic or no readings. There could be a dirt buildup

I'm not familiar with how many pots are in a camera. It would seem there's one attached to the aperture ring, one attached to the shutter ring, and possibly others. Any of them could have these problems. Of course, you also have the light sensor itself and the batteries as well as their associate terminals that could have built up corrosion over the years affecting the reading and connections. Anyone who's seen the buildup of white crud on flashlight battery terminals is familiar with this problem caused by electrolysis caused by power going through dissimilar metals. That could be the problem or add to it.

 

[Kino]

The needle could have sticky residue in it's path or the pivots of the meter needle may be out of socket from a sudden impact; not uncommon for these meters to have foam "bumpers" to cushion the ends of the scale.

If you feel confident enough, remove the top cover and look carefully at the meter needle and it's mechanism to see if any obvious obstructions or debris is fouling the mechanism.

Repair manual: https://learncamerarepair.com/product.php?product=272&category=2&secondary=8

Troubleshooting guide (inside repair manual):

If you have never repaired or attempted to service a camera, please do not attempt to repair it yourself if it is a valued camera. In the end, it's cheaper to have it serviced than invest in all the tools, time and risk of ruining the camera.

If you wish to start repairing/servicing cameras, lay this camera to one side, buy a very dilapidated copy and practice before attempting to fix the one you have.

Do all repairs at your own risk.