Simpson 260 Series Analog Meter

One problem with analog meters not used for some time, is battery leakage on the circuitry. Such was the case with the Simpson 260 in the SFC lab. Upon opening the case and visually inspecting the damage, I noticed that the breaker circuit was corroded. Possibly causing the breaker to trip every time the meter was used.




I dissembled the breaker circuit from the main board, and cleaned off any battery acid that leaked onto the board using contact cleaner and a scraping tool. After I had cleaned the breaker circuit, I noticed that a diode was corroded. Taking the diode out of the circuit, and testing it yielded it to be faulty, and need of replacement.





After replacing the corroded diode, and everything placed back together, the meter was then tested to see if it was still operational. As was suspected, the damaged diode from the leaky battery was the issue.



For testing the Simpson 260, I placed a digital meter in parallel of it while connected to a DC power source. To make the Simpson read more exact, the pointer adjustment was used to set the needle to match the Digital DC voltage. This was not a major change in tuning, but was needed after handing the Simpson 260.
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Simpson 260 Manual

Simpson 260 Schematic