Date: Tue, 9 Jun 1998 10:00:24 EDT
Subject: Meter Repair
In a message dated 98-06-09 08:11:34 EDT, you write:
> In a message dated 98-06-08 21:44:38 EDT, you write:
> << Hi Richard,
> Is there a way of renewing the light cell in those meter?
> Hi Chee,
> Not that I'm aware of. If you display your cameras, this just makes a nice
> addition placed on top of the camera, as it has a mounting piece like the
> bottom of a flash unit. The meter was made by G.E. , has a black casing and
> a chrome top.
There actually are a couple of techniques of restoring selenium cell meters to
some semblence of function. I don't claim to be an expert on this but this is
stuff I've read about others doing with some success.
First, sometimes if the meter still seems to be connected to the cell but is
very weak, wiping the cell down with some acetone will get it going a little
better. I've also heard of polishing the surface of the cell with metal
polish. I have tried the acetone bit on a cell in an Olympus Pen EES2 and it
actually did start working a little better. I suspect what it was mainly
doing was reflowing the conductive track paint and then making better contact
with the substrate.
If the cell is stone cold dead it may be due to the electrical contacts no
longer contacting. One can try resoldering if solder is used or using some of
this paint on conductive track stuff they sell to repair printed circuit
The final technique that I've heard several folks have actually done (though I
haven't tried this myself) is to replace the selenium cell with a chunk of
silicone "solar cell" material that you can get from Radio Shack in a bag of
bits and pieces. As the silicone cell has more output than the selenium cell
one is then able to paint over parts of the cell until it comes into
calibration. Its spectral response is a little different from the selenium
cell but thats probably a minor point to be concerned about.
The above of course applies to both separate meters and cells that are built
into cameras. "Restoring Classic and Antique Cameras" by Alii Service Notes
(available from Porters) has a nice section on how various meters work and
some notes on fixing various meters including replacing selenium cells by
salvaging cells from other cameras or meters. It explains the use of the
conductive paint stuff. The section is illustrated with an Argus A2F and the
ever lovely Autronic, BTW.