Philips VR705/02 - Page 18

ADJUSTMENT INSTRUCTIONS
1.Tape Manager
Set the tape manager number
This setting has to be done after replacement of the EEPROM.
- Call up the service test program, select step 43
- the display shows T-:--:43
using
the
remote
control,
type
in
the
last
tree
digits
of
the
serial
number,
located
on
the
type
plate
of
the
set
press the ok button
exit the service test program.
2. Video signal processing (VS-SEC)
Service tasks after replacement of ICs 7004, 7072:
Before commencing adjustment:
Call the service test program and enter Step 10
(Dummy mode). Remove the drive from the
motherboard.
2.1 3.3 MHz adjustment [3089] (for SECAM)
Purpose: To adjust the mixing oscillator
Consequences of incorrect settings:
Cross patterns in coloured areas, coloured noise.
1.2 MHz sinus
D d
167072")
naan
gia
ae
100mVpp,
R3065
pin 17 playback +5V on IC 7072
6, R3064
Oscilloscope
adjust
to
Video
pattern
optimum
generator
sinus
Sinus generator
A: AC, 50mV/Div, 50ns/Div
IC 7072 Pin 17
2.2 SECAM chrominance record current
adjustment [3088]:
Purpose: To set the optimum record SECAM chroma level.
Symptom, if incorrectly set:
if the record level is too high, beats may appear on the
picture. If the level is too low, the colour may be de-
graded.
| TP | Ady. | MODE | __INPUT
CSRV
Dummy
mode
(VIDEO
IN
E2)
pos.9068
|
R3088
Record Red Picture SECAM
TAPE
Preset E2 75% Saturation
MEAS. EQ. SPEC.
Oscilloscope
Video Pattern A=240 + 15 MVpp,
Generator
Notes: With varying frame amplitudes, the setting is made for the
greatest amplitude.
A: AC, 50mV/Div, 20us/Div