Adjustment Procedures - Grundig K-RCD 120 Service Manual

K-RCD 120

Adjustment Procedures

1. CD-Section
Measuring instruments: Oscilloscope
Note: Do not turn the variable resistor for laser power adjustment. The laser current is pre-set at the factory.
Position of testpoints see page 3 - 9 "CD Board".
Adjustment
Focus Bias Connect the oscilloscope (Volt/Div. DC 0.1V) to testpoint
FA (IC801 Pin57), ground to VREF (IC801 Pin64).
- Close the CD door
- Function switch: CD
Tracking Connect the oscilloscope (Volt/Div. DC 0.5V) to testpoint
EF Balance TB (IC801 Pin53), ground to VREF (IC801 Pin64).
- Load a CD
- Close the CD door
- CD function: Play
2. Cassette Deck
Measuring instruments/equipment: Frequency counter, AF-voltmeter, wow and flutter meter,
Fe test cassette 449 (Part No. 35079-019.00), torque test cassette 456 (Part No. 35079-014.00).
Position of testpoint TP5 see page 3 - 6 "Main Board".
Adjustment
1. Tape speed Connect the frequency counter to the headphone socket.
Insert the test cassette 449, play 3150Hz.
2. Take-up torque Insert the torque test cassette 456.
3. Wow and flutter Connect the wow and flutter meter to the headphone
socket. Insert test cassette 449, play 3150Hz.
4. Head gap angle Connect the AF-voltmeter to the headphone socket.
(Azimuth) Insert test cassette 449,
play 8kHz.
5. Bias frequency Connect the frequency counter to TP5 (R/P Head).
Insert a recordable cassette.
Function: Record-Start.
6. Bias voltage Connect the AF-voltmeter to TP5 (R/P Head).
Insert a recordable cassette.
Function: Record-Start
GRUNDIG Service
Preparations
Preparations
TP5
TP5
Einstellvorschriften / Adjustment Procedures
Adjustment Processs
Set 0V with VR801.
Adjust VR802 so that the graph is symmetrical to the
0-line.
Adjustment Process
With adjustment control (in the
cass.-motor) set the frequency
±
to 3150Hz 0.1%.
Tape tension on: Playback-Start = 35 - 65g-cm
Fast Forward = 50 - 120g-cm
Fast Rewind = 50 - 120g-cm
Deviation < 0.4% (aurally compensated). Playback
measuring time ≥ 30 seconds.
With the head adjustment screw 1 set the
left and right channel to maximum level.
The levels of the two channels mustnot
differ by more than 3dB.
The oscillator frequency should be 150kHz
Adjust with L201.
The bias voltage is 11V.
Adjust with VR202.
V1
o
V2
V1 = V2
1
±
5kHz.
2 - 3