Laser Current - Bang & Olufsen Beogram CD 5500 Service Manual

11-1
Fra apparat nr. 05858372 er CD-lebeveerket eendret
fra en type CDM2 ti! en type CDM4
Ved udskiftning af et CDM2- til et CDM 4-lebeverk
skal lobeverket og servoprintet udskiftes som en
samlet enhed (bestillingsnr. 8420158).
— CD-lebeveerk, separat
~- Servoprint, separat
Bestillingsar. 8420159
Bestillingsnr. 8005264
Laserstram og fokus off-set skal justeres efter
udskiftning af CD-lsbeverk eller servoprint.
Servoprintet pa et CDM 4-lobevzerk er eendret pa
folgende punkter:
Ny veerdi Bestillingsnr.
R3106 4,7 kQ (trimmer) 5370058
R3143 22.Q 5011655
R3145 680 kQ 5011704
R3155 8,2 kQ 5011240
R3159 15 kQ 5010053
R3162 91kQ 5011255
R3163 15 kQ 5010468
C2159 1,5 pF (bipolar) 4200746
C2141 470 nF 4130405
— Der er monteret en modstand (R3214, 220k, bestil-
lingsnr. 5011369) fra ben 6 pa.1C6103 til ben 21
pa 1C6101.
-- Der er monteret en kondensator (C2143, 1,2 nF,
bestillingsnr. 4100283) fra ben 1 pa 1C6104 til ben
5 pa IC6101.
Laserstrem
Vigtigt:
Efter udskiftning af CD lobeverket eller servo-
PCB30 skal laserstrom-potentiometeret 30R3106
forjusteres, inden apparatet, tilsluttes lysnettet.
Tilslut et ohmmeter over 30R3105 + 30R3106. Juster
30R3106, indtil 30R3105 og 30R3106 tilsammen har
en verdi pa 1 kQ.
Tilslut et DC-voltmeter over 30R3102.
Tilslut et oscilloskop til ben 27 pa 301C6101.
Tleg testplade nr. 5 (plade uden fejl, bestillingsnr.
3634031) og tryk PLAY.
Kontroller pa oscilloskopet, om der er HF signal.
Hvis der ikke er HF signal, slukkes apparatet, og
fejlen findes,
Hvis der er HF signal, spilles spor 1 pa testplade 5,
og 30R3106 justeres, til der males 50mV +5mV med
.-.D€-volimeteret,
Bang & Olufsen
From unit no. 05858372 the CD drive mechanism
has béen changed from a CDM2 model to a CDM4
model.
When replacing a CDM2 model with a CDM4
model the drive mechanism and the servo PCB are
to be replaced as a single unit (part no. 8420158).
Part no. 8420159
Part no. 8005264
- CD. drive mechanism, separate
- Servo PCB, separate
The laser current and focus off-set must be adjusted
after the CD drive mechanism or servo PCB has
been replaced.
The servo PCB of the CDM4 drive mechanism has
the following modifications:
New value Part no.
R3105 47 kQ (trimmer) 5370058
R3142 22Q 5011655
R3145 680 kQ 5011704
R3155 8.2kQ 5011240
R3159 15 kQ 5010053
R3162 91 kQ 5011255
R3163 15 kQ 5010468
C2159 1.5 pF (bipolar) 4200746
C2141 470 nF 4130405,
~ A resistor (R3214, 220k, part no. 5011369) is
mounted between pin 6 on 1C6103 and pin 21 on
1€6101.
- Acapacitor (C2143, 1.2 nF, part no. 4100283) is
mounted between pin 1 on 1C6104 and pin 5 on
1C6101.
Laser current
Important:
When replacing the CD mechanism or the servo
PCB30, the laser current potentiometer 30R3106
must be preadjusted before the set is connected to
mains.
Connect an ohmmeter across 30R3105 + 30R3106.
Adjust 30R3106 until the combined value of
30R3105 and 30R3106 is 1 kQ.
Connect a DC voltmeter across 30R3102.
Connect an oscilloscope to pin 27 of 301C6101.
Load test disc no. 5 (disc without faults, part no.
3634031) and press PLAY.
Check on the oscilloscope whether there is any HF
signal. If not, switch off the CD player and locate the
fault.
Tf there is an HF signal, play track 1 of test disc 5
and
~~""is obtained on the DC voltmeter.
st-30R3106 until a reading of 50 mVt5 mV