Philips AS98 Service Manual
For internal use only PHILIPS
ISSUE AS98.04 (98-03-17)
Published by:
Service Depar tment Audio Systems
LINE OF BUSINESS AUDIO SYSTEMS
04.01 TYPENUMBER(S): AS660C, AS665C, AS670C, AS675C, AS760C, AS765C,
AS785C, FW315C, FW340C, FW352C, FW355C, FW365C,
FW372C, FW373C, FW375P, FW392C, FW395C, FW710C,
FW725C, FW730C, FW745C, FW750C, FW770P, Fw780P,
FW790P
INFORMATION : In above mentioned sets the 3CD Carousel Changer module
“3CDC DH” has been replaced by the “3CDC MG” module.
This has been published with following Service Informations:
A97-164 for FW725C, FW730C
A97-165 for FW745C, FW750C
A97-166 for FW770P
A97-167 for FW780P
A97-168 for FW790P
A97-169 for FW710C
A97-170 for FW365C
A97-172 for FW355C
A97-173 for FW375P
A97-174 for AS660C, AS665C
A97-175 for AS760C, AS765C
A97-180 for FW352C
A97-182 for FW372C
A97-183 for FW392C
A97-184 for FW395C
A97-185 for FW373C
A97-187 for AS670C, AS675C
A97-188 for AS785C
A97-189 for FW315C
A97-190 for FW340C
In all Service Informations the service codenumber for the flex-foil,
pos. 8002, is missing:
8002 4822 320 11974 flex-foil 15pole (length=190mm)
Attention: Above mentioned flex-foil is not compatible to the flex-foil
used in the old 3CDC DH module!
REMARKS :
SERVICE NEWSLETTER
Service Newsletter 1998 – Audio Systems 1/5
04.02 TYPENUMBER(S): CDR870
INFORMATION : The Recording Test disc
Problems concerning the recording facilities of the CDR870 can be
checked by using a blank Digital Audio CD-ReWritable disc.This disc
can be re-used afterwards and the CD-RW recording strategy does
not deviate strong from the CD-R writing process.To define whether
the set is working proper this disc can be read after recording and
even after finalising.
To ERASE complete disc use the service test program and actuate
simultaneously <ERASE> and <RECORD> keys together with
<POWER ON>.This will take about 37 minutes because erasing is
done at double disc speed.
REMARKS :
04.03 TYPENUMBER(S): CDR870
INFORMATION : CDR870 is not able to play CD R/W discs, recorded and finalised via
a computer.The CDR870 display shows “No Audio”.
Explanation:
The audio bit, standing in the ATIP pregrove, is checked before
starting up. In case of a final finalised CDR disc, the ATIP (Engine) is
switched off. So the application can not reach this information
anymore.
In case of CD R/W, ATIP must always be active (to allow Erase
DISC). So the audio bit will be detected by the application when
starting up this disc.
Because the audio bit is not detected in this case, the display shows
the message "NO AUDIO".
This is not an error but a too strong implementation of the law. In fact
you may not record audio on a general purpose disc with a CDR870.
REMARKS : In the future reading audio from a general purpose disc will be
allowed. (CDR760 ....)
Service Newsletter 1998 – Audio Systems 2/5
04.04 TYPENUMBER(S): CDR870
SYMPTOM :
Bad recording when using optical input of set
CURE : This problem is caused by the optical input device PLR102
(item 1520 on the connector PCB). In case the risetime specification
is worse than 50ns, the optical input signal may result in a bad
recording.There are 2 solutions possible:
1. Replace PLR102 by TORX174 (Toshiba) with service codenumber
4822 130 91224. C2508 has to be replaced by a shor t circuit to
ground.The risetime specifications of this device are <30ns.
2. Use one of the free inverter ports of device 74HCU04N (item 7500)
to improve the optical in signal.This can be done as follows:
• Connect output 4 of optical device to pin 9 of IC7500.
This pin must be lifted from the PCB.
• Connect pin 8 of IC7500 to pin 14 of connector 1500.
• Interrupt copper track between pin 14 of connector 1500 to pin 4
of switch 1522 (not mounted).
With this solution, steep flanks will be created on the signal.
Note that inverting is no problem for a biphase signal.
See also picture of the modified PCB below.
REMARKS : An improved connector PCB will be introduced in course of
production. See Service Information A98-250 (4822 725 25244).
2510
3509
3515
3517
3508
3510
3511
3513
2511
2512
2513
2505
3506
2502
2503
2507
3503
4500
3500
3501
3502
3507
2500
2508
2509
1234
1234
A A
2500 A 1
2502 A 2
2503 A 3
2505 A 3
2507 A 3
2508 A 2
2509 A 2
2510 A 4
2511 A 4
2512 A 4
2513 A 4
3500 A 1
3501 A 1
3502 A 1
3503 A 3
3506 A 3
3507 A 2
3508 A 3
3509 A 4
3510 A 4
3511 A 4
3513 A 3
3515 A 4
3517 A 4
4500 A 2
cut track
1
2
1530
1531
7501
7502
7503
7504
3516
3518
3512
3514
3504
35052504
2506
7500
5450
1522
1500
2501
15201521
1234
1234
A A
1500 A 3
1520 A 1
1521 A 1
1522 A 2
1530 A 4
1531 A 3
2501 A 2
2504 A 3
2506 A 3
3504 A 3
3505 A 3
3512 A 4
3514 A 3
3516 A 4
3518 A 3
5450 A 2
7500 A 3
7501 A 4
7502 A 4
7503 A 3
7504 A 4
4T
1S
2S
MT
1T
2T
3T
1
5
4
2
3
16
T
1
44
1
R
lift pin from PCB
6652IRIS CODE
Service Newsletter 1998 – Audio Systems 3/5
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