| Author | Message | ||
     M_currie Tinkerer Username: M_currie Post Number: 124 Registered: 07-2006 Rating: N/A |
Ok, here it is to the best of my ability. I opened up a Master IV which has been reading a little low but still has life in it. I gained access to the connections for the meter by removing the back plate and the hinged door over the photocell. The body of the meter is negative, and the zero adjust tab of the movement is positive. I found a light source that put the meter to full scale, then measured the voltage with that source hitting the cell. It came to about 150 millivolts. I cannot guarantee that reading to the last millivolt, but it was pretty close. I did not try to find a variable voltage source and actually run the meter with it, because the connections here are pretty delicate, but I hope this helps. OK, now I am going to try to put my Master IV back together. |