Proline 1405 R Service Manual

PROLINE 1405 R
General Information
PC 180 "Nova" Chassis

Focusing

Adjustments

Adjust the pontentiometer on the EHT trans-
former in order to obtain the best focus condi-
(PC180 CHASSIS)
tions.

Power Supply

White setting

Conditions: Use a staircase black/white signal
Conditions: Set brightness and contrast to the
and set the Colour, Brighhtness and Contrast to
minimum (dark condition).
obtain a normal picture.
- Adjust P701 and P702, if present, to obtain
Operations: Adjust P401 to obtain, on C420
the maximum video signal on T701-T704-
(TP111), the following value:
T707 collectors.
105VDC± 1V when diode D410A present on
chassis.
Operations: Adjust P701 and P702 to obtain a
118VDC± 1V when diode D410 present on
grey level staircase without any colour.
chassis.
Note: on chassis is present D410 or, alternately,
D410A.

Video Frequency (IF):

Conditions: Apply a standard modulated IF
signal of 50 mV amplitude to the CH501.
Operations: Connect a balanced oscilloscope
probe on pin 19 scan connector.
- Connect a voltmeter on pin 9 of C11.
- Adjust L101 to read 2.5 V on voltmeter and to
obtain the best signal on oscilloscope.

Tuner AGC

Fig 1.
Conditions: Tune a channel at the end of
BAND III (e.g. channel E11) with RF input of
1mV.
- Connect a voltmeter to C508.
Operations: Set P101 full on counterclockwise
and check that the voltage is about 8W.
- Adjust then P101 to obtain a reduction of the
previous measured voitace of 300mV.

Adjustment of geometry control parameters

Conditions: monoscope or cross hatch signal
from antenna and normalised brightness,
contrast and colour.
Operations:
- Adjust P303 for vertical shift correction.
- Adjust P302 for vertical amplitude correction.
- Adjust P301 for vertical correction.

Automatic Cut-Off

Conditions: Normal TV signal.
- Set the Colour, Brightness and Contrast to
minimum setting. Check, with oscilloscope,
the dc voltages of cut-off pulse visible during
the vertical blanking on collectors of T701-
T702-T703 and select the higher pulse (see
Fig. 1).
Operations: Adjust the cut-off pulse with G2
potentiometers (on the EHT transformer) to
obtain the following level:
- 150VDC if the power supply of the video
amplifiers (TP160) is 190VDC
- 130VDC if the power supply of the video
amplifiers (TP160) is 160VDC
- 115VDC if the power supply of the video
amplifiers (TP160) is 140VDC
Text Diagram
Waveforms