2.3. Electrical checks for CD Player Note: Do the same check for CD Player Nos. 1 to 3.
STEP ITEM SIGNAL SOURCE OUTPUT CONNECTION ADJUSTMENT � REMARKS
1
Laser Current ABEX Test Disc DC Voltmeter Check TCD-784 across R101 on CD P.C.B.
1. Turn ON the power and load a test disc. (To load the test disc, press the Open/Close button of the CD Player.) 2. Play back the test disc and calculate the current flowing into R101 on the CD P.C.B. Ass'y from the following formula. Voltmeter Value I(Measured) = = oo.o mA R101 (10 Ohms) Example: 510.3 (mV) I(Measured) = 10 (ohms) 3. Check that the I(Measured) obtained in 2 and the rated current value (IOP) shown on the label are almost the same. [How to read IOP on the label] The shaded "OOO" on the label shows the IOP. If "OOO" is 475, the IOP is 47.5mA. NOTE: The calculated current (I(Measured)) = 51.03 mA
KSS-540A
IOP(oo.omA)
Laser Pickup KSS-540A
should be in a range of 30 to 60 mA. If the value is large, the pickup will be defective. 4. Stop the test disc.
2 EFM Signal Adjustment ABEX Test Disc Oscilloscope TCD-784 between pin 1 of TP101 and GND on CD P.C.B. � 1. Play back the first track of the test disc. 2. Be sure that the peak-to-peak value of the EFM waveform is approx. 1V.
Approx. 1Vp-p
Oscilloscope Setting: AC Mode, 0.2 V/div, 0.5 µs/div 3. Stop the test disc and eject it.
