JBL PSW-D110 Service Manual page 12

4. High-Pass
-Set up Set Generator at 100mV@at 100Hz
Signal to Low level input
Measure voltage at high-pass output
-Voltage measurement
4. LED
With a 35mV input signal at a single Low level input, LED should change to green
See flow chart (following page) for detailed diagnostics.
Hi-Pass Pot Setting
CW
CCW
Output
24mV
55mV
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