JBL E250P, Руководство по обслуживанию

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- Voltage measurements
OP AMP
U2(1) U2(14) U2(8) U3(7) U3(1) U3(14) U3(8) U5(7) U5(1)
SPEAKER
O/P
306.9mV 461mV 460mV 658mV 628mV 598mV 2.326V 2.02V 3.57V 23.33V
2. High Level Input Sensitivity
-Set up Turn level, X’OVER FREQ POT Fully CW and LFE switch off
Set Generator at 1.3V@50Hz
Signal to High level input
-Voltage measurements 15.3V at speaker output
3. Low-Pass
-Set up Set Generator at 200 mV@100Hz
Signal to
Line
level input
Measure voltage at S+ speaker output
-Voltage measurement
X’OVER FREQ. Setting Output
CW 14.03V
CCW 4.8V
4. LFE
-Set up Set Generator at 200mV@200Hz
Signal to
Line
level input
Measure voltage at S+ speaker output
LFE switch Setting Output
Normal 6V
LFE 18.32V
See flow chart next page for diagnostics.
E250P
14
DETAILED TROUBLESHOOTING (CONT'D)