Catman, Quality Light Metric has been mentioned once, I think, so far in this thread. There's a law of nature that a newly purchased used light meter is always off calibration.

QLM does outstanding work, here's http://www.whitepages.com/business/q...s-angeles-ca-1 a link with their contact information.

If you want to use the meter, have it overhauled properly, don't go for any of the half-assed expedients that we all love.