Psw-D110/Dps-10 Power Amp Test Procedure And Flow Chart - JBL PSW-D110 Service Manual

A. Power Amp Section
1. Resistance Check
2. Power Up LED RED
3. D.C. Operation
Voltage measurements (DVM)
Between +6V V+
And V- GND
Should be
+6.2V +43.5v
Reading
4. Check Switching Frequency
Use scope (EITHER USES AN ISOLATION TRANSFORMER OR ATTACHES THE PROBE TIP TO SPK- and
REFERENCE LEAD TO SPK+)
-Reading 100kHz +/-10%,1Vpp
B. Pre Amp Section
1. Low Level Input Sensitivity
-Set up Turn level and Low-Pass Pot Fully CW
Generator set at 50mV@43Hz
Signal to Low level input
-Voltage measurements
U1(1) U1(8)
415mV 395mV
2. High Level Input Sensitivity
-Set up Turn level and Lo Pass Pot Fully CW
Set Generator at 2.55V@43Hz
Signal to High level input
Voltage measurements 14.5V at speaker output
3. Low-Pass
Set upSet Generator at 100mV@100Hz
Signal to Low level input
Measure voltage at speaker output
Voltage measurements
Low-Pass Pot Setting
CW
CCW
PSW-D110/DPS-10 TEST PROCEDURE
Resistance from O/P of the module to GND should be >10K (NO LOAD)
Resistance from V+ of the module to V- of the module should read >5k
Resistance from V+ of the module to O/P of the module should read >10K
Resistance from V- of the module to O/P of the module should read >10K
O/P V-
GND GND
0V -43.5V +15.5V
OP AMP
U1(14) U1(7)
590mV 603mV
Output
11.1V
5.37V
+15V S/D FR
GND V- GND
+5.75V 0V
U2(1)
5.73V
I/P GND -15V
GND GND GND
-15.5V
0V 0V
SPEAKER
O/P
U2(7)
5.2V 14.5V
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