Power Meter intermittent
 

MC2205 Power Meters

Have recently switched to low-power listening with McIntosh tuners, and now find the LEFT power meter is cutting out (dropping to zero) below 0.02 watts, or -35 to -40 dB from max rated. I've checked for meter drive signal on pins 11 & 12 of the Lamp PC Board with an o-scope, and both circuits have drive voltage, even when the LEFT meter is out.

http://home.comcast.net/~mc_audio/MC...eter_wires.jpg
MC2205 meter drive pins.

Cycling the Speakers OFF/ON restores the meter movement (and puts a substantial transient on the meter circuit.) Does this mean a faulty meter movement? Any remedies?


-Gregory

Meter range switches tend to never get used thus the contacts get corrosion and intermittents. Work the switch and if you have some give it a shot of DeOxit D5.