PHILIPS FWC500
Instrukcja Serwisowa

TAPE ADJUSTMENT & CHECK TABLE

HEADPHONE BOARD - COMPONENT LAYOUT

HEADPHONE BOARD - CHIP LAYOUT

TEST CASSETTE

RECORDER MODE

MEASURE ON

ADJUST READ ON with to

ADJUST MOTOR SPEED
NORMAL SPEED SBC420 3150Hz PLAY B PLAY A 1 or 2 frequency counter 3620 check 3150Hz +/- 0.5% 3150Hz -0.8/+1.8%

LEFT RIGHT

CHECK WOW & FLUTTER
This assembly drawing shows a summary of all possible versions. For components used in a specific version see schematic diagram and respective parts list.
This assembly drawing shows a summary of all possible versions. For components used in a specific version see schematic diagram and respective parts list.

DECK A & B

SBC420 3150Hz

PLAY

1

or

2

W&F-meter

check

<0.4 % DIN

LEFT RIGHT

ADJUST AZIMUTH
DECK A & B SBC420 10kHz PLAY FWD PLAY REV # 1 or 2 mV-meter left hand screw right hand screw max. output level & left=right

LEFT RIGHT

CHECK PLAYBACK FREQUENCY RESPONSE
5852
3139 113 3447 pt2 dd wk0119
3139 113 3447 pt2 dd wk0119

DECK A & B

SBC420

PLAY

1

or

2

mV-meter

check

limits see fig.1

LEFT RIGHT

ADJUST BIAS CURRENT

HEADPHONE BOARD - CIRCUIT DIAGRAM
DECK B
1850 C1 1851 B3 1890 A3 1891 C3 1892 C3 2850 A2 2851 A3 2852 A2 2853 A2 2854 C3 5850 B1 5851 A2 5852 B2 9550 A2

SBC419A^ RECORD SBC420

5

or

6 mV-meter

3773 check

995mV 750mV +/- 1.5dB

LEFT RIGHT

CHECK OVERALL FREQUENCY RESPONSE AND DISTORTION
Inject 3mV signals 100Hz, 250Hz, 1kHz, 10kHz, 12.5kHz via 3 or 4 RECORDED CASSETTE 1 or 2 SBC419A^ or SBC420

1
# : Provision ## : Provision for ESD

2
# 9550 2850 22n 5851 2u2 HP 2852 22n 2853 100n

3

RECORD B

Note : Some values may varies, see respective parts list for correct value.

2851 22n

PLAY B

mV-meter

check

limits see fig. 2 *

A

A
1890 1 RT-01T

LEFT RIGHT RECORD B

Inject 1kHz 8.85mV via 3 or 4

SBC419A^ or SBC420 RECORDED CASSETTE

9 7 8

PLAY B

1

or

2

THD-meter

check

<3% *

LEFT RIGHT
1 2 3 1851 TC38

B
5850 2u2 2u2

4 5 6

B

SBC419A^ : 4822 397 30069 SBC420 : 4822 397 30071

# For Auto-reverse version only * If high frequencies are not within limits, decrease bias and re-measure. If distortion is too high, increase bias and re-meaure ^ Not applicable for Ferro version
level(dB)

TO AF9
1850
HP_DET
1 2 3 4

level(dB)

HP

C

HP_RIGHT HP_GND HP_LEFT

C
##1891 ##2854 RT-01T 1 FE-BT-VK-N HP
3139 118 54300...for 89620...3447 pt2 dd wk0119

8dB

6dB

8dB

8dB 10dB (HSD)

6dB

8dB 10dB (HSD)

##1892 1 RT-01T

470n

80

250 figure. 1

4k

12.5k

f(Hz)

100

250 figure. 2

4k

10k

f(Hz)

1

2

3