Philips VR120 Service Manual page 55

Soldering iron
C.B.A.
Figure 5-7
c. Solder all pins of the Flat Pack IC. Make sure that none of
the pins have solder bridges between pins on the Flat Pack
IC.
5.4 Note
All integrated circuits and many other semiconductor devices
are electrostatically sensitive and therefore require the
special handling techniques described in the "SAFETY
INSTRUCTIONS" section of this manual.
5.5 Voltage measurements
Color bar signal in SP REC and PB modes.
Note:
Voltage indications for the REC. and PB mode on the
schematic diagrams are shown below:
PLAY mode
REC mode
Figure 5-8
Service modes, Repair tips
Presolder
Flat Pack IC
REC and PLAY mode
(identical voltages for
both modes)
VR120
5.6 How to read wave forms
1
Connecting point
2
Aplitude
3
Time base
4 Operating mode of the VCR
2
1
Figure 5-9
5.7 Voltage indication of Zener diodes
The Zener voltage of Zener diodes is indicated as such on
schematic diagrams:
Example: BZX79C20............Zener voltage: 20 Volts
5.8 How to identify connectors on schematic
diagrams
Each connector is labeled with a connector number and a pin
number indicating to what component it is connected; in other
words, its counterpart.
Use the Connecting Wiring Diagram to find the connections
between associated connectors.
Example:
The connections between C.B.A.s are shown below:
Connector no.
and Pin no.
on PCB
1913
1
MOT1
1
MOT3
1
MOT2
1
MOT0
1
POS
Figure 5-10
5. GB 55
4
3
PCB to which this
connector is connected
Connector no. to which
the left connector is
connected