Saturday, February 2, 2013


1) The needle itself is 'stuck' to one side. This is typical after 50+ years of dirt and grime. The needle can 'stick" to the plastic stop(s) on either side the galvanometer. 

Next time it happens, try rotating the ASA dial all the way in one direction and then the other, and finally back to your normal ASA setting. If the needle was stuck, this will usually dislodge it.
The permanent cure is to remove the eyepiece diopter, and very carefully, clean the sides of the needle with a small swab soaked in alcohol. If you can see a 'fuzzy edge' on either side of the needle, the needle needs cleaning.

2) The battery adapter is sometimes built from a stack of washers. The contact points between the washers corrode or otherwise don't make electrical contact. This causes an interruption in the battery circuit and the needle won't function. loosening and retightening the battery cover may fix the problem temporarily.

3) The 'U' shaped spring at the bottom of the battery well is permanently flattened. This can happen if the adapter length is too long. Sometimes the spring is broken in half at the bend point, and an adapter is/was made to take up the difference in length.
There will not be any tension from the spring so contact will depend on the battery cover being screw down tightly. If it is screwed down too tight, the spring holder (plug) itself will be pushed away from making a good ground connection and the circuit may be interrupted.
4) Corrosion on the connections inside the camera located on the backside of the plug is causing an intermittent open. There are (2) wires. One connected to the grounding ring and 1 is connected (soldered) to the rivet holding the spring to the plug. 
If there is sufficient corrosion, the wires can corrode and may have intermittent contact. The fix is to replace the wires and/or the plug.

5) There is corrosion on the ground ring that is in between the plug and the camera body. The corrosion is caused typically by a mercury battery being left in the camera for too long and subsequently leaking creating a greenish-whitish powder-like coating. 
This corrosion can be 1) on the threads of the cap and body or, 2) on or near the spring in the battery well. Sometime the corrosion is superficial and while present, sometimes doesn't cause any problems. 

If corrosion is present, the battery contacts and related parts should be cleaned thoroughly. You can swab the battery well with plain vinegar, which is 5% acetic acid, and the acid will dissolve the corrosion. Swap again with alcohol several times to remove any trace of the acid. Let all air dry.

When installing a new spacer kit and replacement Zinc Air Cell, be sure the spring in the battery well is in good operating order. If it is bent flat or damaged, it should be replace. 

The kit sold by is designed to be a direct replacement for the original mercury cell, and it depends on the spring being in good operating order. 

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