Universum FT-81015, Руководство по обслуживанию

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2
DO NOT CHANGE ANY MODULE UNLESS THE SET IS SWITCH OFF
The mains supply side of the switch mode power supply transformer is live.
Use an isolating transformer.
The receivers fulfill completely the safety requirements.
Safety precautions:
Servicing of this TV should only be carried out by a qualified person.
- Components marked with the warning symbol on the circuit diagram are critical for safety and must only be replaced
with an identical component.
- Power resistor and fusable resistors must be mounted in an identical manner to the original component.
- When servicing this TV, check that the EHT does not exceed 26kV.
TV Set switched off:
Make short-circuit between HV-CRT clip and CRT ground layer.
Short C804 (150mF) before changing IC802 or other components in primary side of SMPS.
Measurements:
Voltage readings and oscilloscope traces are measured under following conditions.
Antenna signal 60dB from colourbar generator. (100% white, 75% colour saturation)
Brightness, contrast, colour set for a normal picture.
Mains supply, 220VAC, 50Hz.
PERI-TV SOCKET
SCART 1 (SC050) SCART 2 (SC051)
1 Audio right output 0.5Vrms / 1K 1 Audio right output 0.5Vrms / 1K
2 Audio right input 0.5Vrms / 10K 2 Audio right input 0.5Vrms / 10K
3 Audio left output 0.5Vrms / 1K 3 Audio left output 0.5Vrms / 1K
4 Ground AF 4 Ground AF
5 Ground Blue 5 Ground Blue
6 Audio left input 0.5Vrms / 10K 6 Audio left input 0.5Vrms / 10K
7 Blue input 0.7Vpp / 75ohm 7 Blue input 0.7Vpp / 75ohm
8 AV switching input 0-12VDC /10K 8 AV switching input 0-12VDC /10K
9 Ground Green 9 Ground Green
10 - 10 -
11 Green input 0.7Vpp / 75ohm 11 -
12 - 12 -
13 Ground Red 13 Ground Red
14 Ground Blanking 14 Ground Blanking
15 Red input 0.7Vpp / 75ohm 15 -
16 Blanking input 0-0.4VDC, 1-3VDC / 75ohm 16 -
17 Ground CVS output 17 Ground CVS output
18 Ground CVS input 18 Ground CVS input
19 CVS output 1Vpp / 75ohm 19 CVS output 1Vpp / 75ohm
20 CVS input 1Vpp / 75ohm 20 CVS input 1Vpp / 75ohm
21 Ground 21 Ground
INTRODUCTION
11Ak28 is a 100Hz flicker free colour television capable of driving 28”4:3/16:9, 33”4:3 and 29”4:3 real flat picture tubes.
The chassis is capable of operation in PAL, SECAM, NTSC (playback) colour standards and multiple transmission standards
as B/G, D/K, I/I’, and L/L´.Sound system output is supplying 12W (10%THD) for left, right and center outputs of 8ohm speakers,
and 2 x 7W for surround outputs of 2 x 4ohm speakers, connected in series.
TV supports the hightext (level 2.5) teletext standard. It is possible to decode transmissions including high graphical data.
The chassis is equipped with one full EuroScart, two other SCARTs for AV input/output, one front-AV input, one back-AV output,
one headphone output, one SVHS input (via SCART and SVHS connector), one VGA input, two external speaker outputs (left
and right), one centre speaker output, and one surround speaker output for two speakers in series.