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AMSTRAD STV 20E
General Information Combination TV & Satellite Receiver Matrix
Item See Model Book
5: 1H Delay Line Safety Notes .......................................................................... Amstrad STV 2104 5 Alignment Points: VR10, L11 Fig. 3
1
This level starts Notes: 1: Be sure the tube surface faces East. 2: Make this adjustment under European magnetic field, (Vertical: 0.4G, Horizontal: 0.2G). 3: Always adjust Sub-Bright, V-Size, Cut-Off and PAL. 4: The allowable range during chroma temperature adjustment should be ±5% max. Y: 0.285 to 0.315 X: 0.275 to 0.305. 7: SECAM Chroma Bell Filter Fig. 9 Alignment Points: L12 Alignment Method: 1: Input the SECAM colour bar signal. 2: Turn the contrast, brightness and colour to max. 3: Connect the oscilloscope as in the following drawing. 4: Adjust L10 with core driver to meet same level with a (blanking) and I (white) as in the following drawing. Ref: Vp-p Adjustment Measurement Apparatus: Test Point: Adjusted Point: Adjustment Methods: Ref: Fig. 10 10: B-Y Demodulate Coil Alignment Points: L9 Alignment Method: 1: Input the SECAM colour bar signal. 2: Turn the contrast, brightness and colour to max. 3: Connect the oscilloscope as in the following drawing. Video Level Adjustment Input C/N: Modulated Signal: Measurement Apparatus: Test Point: Adjusted Point: Adjustment Methods: Ref: 2: Connect F-counter to from the 17th pin to the 20th pin. 3: Adjust C27 as the frequency to be 87381.3334 ± 0.5 Hz.
Alignment Instructions
+5V Adjustment Measurement Apparatus: Test Point: Adjusted Point: Adjustment Methods: Voltage Meter 5V adj. PP 02 Adjust to get +5V Fig. 2 Voltage Meter VPP Adj. PP 01 Adjust to get +21V (test mode 5). Fig. 2 20dB< Multiburst Oscilloscope Pin jack (PAL B.B) VR701 Fig. 1
Recommended Safety Parts
Item
IC1901 L1001 L1901, L1902 SW1901 T1002 AC1901 F1901 RE1901 PS1901 T1901 CRT1001 C1027 C1053 C1212,1213,1214 C1901,1902 C1079 C1078, 1079 C1061 R1093, R1094 R1946, R1998 R1071, R1999 R1091 R1082 R1907 R1908 R1095 R1096
Part No.
241031 241206 241210 241188 241174 241257 152603 241177 241178 241258 240778 241199 241200 157738 157794 254672 157741 194214 1420154 241243 241224 157545 241226 241244 241245 241246 241227
Description
IC STK73907 Switching PSU Coil Pot Type 4.7uH 117M957 Line Filter TE002 SW Power 3350 FBT 1813481 AC Cord Fuse 4A (T) 250V Power Relay Posistor 5790117 Power Transformer Switching CRT/GS/SAM, 20" Capacitor 60pF Trimmer Capacitor 2.2uF 25V Tantal Capacitor 0.47uF Film Capacitor 0.1uF 250V Polypropylene Capacitor 0.0033uF 1.6KV Polypropylene Capacitor 0.0047uF 1.6KV Polypropylene Capacitor 0.47uF 200V Fuse Resistor 1 ohm 1/2W Fuse Resistor 1.2 ohm 1W Fuse Resistor 2.2 ohm 1/4W Fuse Resistor 2.2 ohm 1W Fuse Resistor 68 ohm 1/2W Cement Resistor 0.47 ohm 5W Cement Resistor 1 ohm 5W Cement Resistor 3.3K ohm 5W Cement Resistor 3.9K ohm 5W
Alignment Method: 1: Input the Phillips pattern. 2: Connect the oscilloscope to IC5 pin 62 (synchronise the oscilloscope externally through the D13 anode). 3: Adjust VR10, L11 so that the amplitude at Anti-PAL signal part becomes minimal (no colour) and the waveform at the colour bar part is not seen in double (Venetian Blind does not appear at the colour bar signal). See Fig 4.
Fig. 6 4: Adjust L12 with core driver to flat wave from at arrow marked on following drawing. Fig. 4 6: White Balance
Service Adjustments
Note: The colour, contrast and brightness controls, unless otherwise specified, should all be set to centre. 1: Focus Alignment Points: Focus VR Alignment Method: 1: Input monoscope pattern. 2: Align the focus whilst using the figure 325 (indicating number of the resolution) at the upper left of the monoscope pattern as reference, and check to ensure that no fading is detected in the centre and all four corners. (set the Contrast/Bright control to centre)
horizontal green line starts flashing. 5: Adjust VR301 (blue) and VR304 (red) until the horizontal line turns white. 6: Turn the service switch off. Note: At this time, each vol. of R. Drive (VR305) and B. Drive (VR302) should be in the centre. 3: V. Size Alignment Points: VR11 Alignment Method: 1: Input monoscope pattern. 2: Adjust VR11 so that the monoscope V. Size display becomes 92%. 3: Align horizontal/vertical balance and then adjust so that the circle in the monoscope pattern centre becomes truly round.
Alignment Points: 1: VR301, VR303, 2: VR304 3: VR302, VR305 Alignment Method: 1: Input APL 100% white. 2: After ageing for 20 - 30 mins, demagnetise the tube (CRT) surface with a de-magnetiser. 3: Set the colour analyser to the CHROMA mode, and after zero point calibration, bring the optical receptor into close contact with the centre of the tube surface (CRT) and adjust R. Drive (VR305) and B. Drive (VR302) so that the respective chroma temperatures become 80000 , K-10MPCD (X: 0.300, Y: 0.290). 4: Turn the service switch on. 5: At this time, check that the horizontal line is white. If it's not white adjust the Cut-Off VR, VR301 (blue), VR304 (red), VR303 (green) until proper alignment is reached. 6: Turn the service switch off, and using the colour analyser, check that the chroma temperatures read the pre-set values. 7: Repeat steps 3 - 6 above, and adjust so that the settings of chroma temperature and horizontal line are at their best.
Fig. 7 8: IDENT Coil Fig. 11 Alignment Points: L13 Alignment Method: 1: Input the SECAM colour bar signal. 2: Turn the contrast, brightness and colour to max. 3: Connect the oscilloscope as in the following drawing. 4: Adjust L9 with core driver to meet same level with a (blanking) and I (white) as in the following drawing.
Video Frequency Response Adjustment Input C/N: 20dB< Modulated Signal: Multiburst Measurement Apparatus: Oscilloscope Test Point: Pin jack (PAL B.B) Adjusted Point: CT 701 Adjustment Methods: Adjust to get a flat video frequency response (0.5 - 4.8 MHz) Ref: Fig. 1 Audio Level Adjustment: Input C/N: Modulated Signal: Measurement Apparatus: Test Point: Adjusted Point: Adjustment Methods: Ref: 20dB 1 kHz Sin Wave Oscilloscope Pin jack (L, R) L: VR301, R: VR302 Adjust to get 2Vp-p audio level Fig. 1 8 dB Colour Bar Monitor TV Pin Jack (PAL B.B) VR101 Adjust to get 1332 on frequency display with 1332 MHz input frequency Fig. 1
Fig. 12 11: On Screen Point Adjustment Alignment Points: L8 Alignment Method: 1: Input colour bar. 2: Indicate "On Screen" as to be a bar, with Picture Select key. 3: Adjust L8 as the distance between both the ends of On Screen and "Escusscattion" to be same. 12: Clock Adjustment Alignment Points: C27 Alignment Method: 1: Short between the 17th pin and 20th pin of IC3 with diode.
*connect AC-code and remove code off.
Align the focus with this figure serving as a standard
Fig. 8 4: Adjust L13 with core driver to peak DC voltage. 9: R-Y Demodulate Coil
Fig. 1 2: Cut Off Alignment Points: VR301, VR302, VR304, Screen VR. Alignment Method: 1: Input APL 100% white. 2: Set the screen (counter-clockwise), VR301 and VR304 (counter-clockwise) to minimum. 3: Turn the service switch on. 4: Adjust the screen to a point where the
Fig. 2 4: Sub. Bright Alignment Points: VR12
AFC Adjustment: Input C/N: Modulated Signal: Measurement Apparatus: Test Point: Adjusted Point: Adjustment Methods:
Alignment Points: L10 Alignment Method: 1: Input the grey scale. 2: Set contrast and brightness to centre. 3: Adjust VR12 to point where the level one step higher than the black level starts flashing. Alignment Method: 1: Input the SECAM colour bar signal. 2: Turn the contrast, brightness and colour to max. 3: Connect the oscilloscope as in the following drawing.
Ref:
Fig. 5
Adjustments / Safety Parts / Main Diagram / Power Supply / Power Supply (Sat Rec) / Audio Diagram / Tuning CPU / Audio Interface / Tuner & RF (Sat Rec)
AMSTRAD STV 20E
Main Diagram
2
Adjustments / Safety Parts / Main Diagram / Power Supply / Power Supply (Sat Rec) / Audio Diagram / Tuning CPU / Audio Interface / Tuner & RF (Sat Rec)
AMSTRAD STV 20E
3
Power Supply & Front Display Diagram
Adjustments / Safety Parts / Main Diagram / Power Supply / Power Supply (Sat Rec) / Audio Diagram / Tuning CPU / Audio Interface / Tuner & RF (Sat Rec)
AMSTRAD STV 20E
Audio PCB Diagram
4
Tuner & RF (Satellite Receiver) Diagram
Power Supply (Satellite Receiver) Diagram
Adjustments / Safety Parts / Main Diagram / Power Supply / Power Supply (Sat Rec) / Audio Diagram / Tuning CPU / Audio Interface / Tuner & RF (Sat Rec)
AMSTRAD STV 20E
5
Tuning CPU Diagram
Adjustments / Safety Parts / Main Diagram / Power Supply / Power Supply (Sat Rec) / Audio Diagram / Tuning CPU / Audio Interface / Tuner & RF (Sat Rec)
AMSTRAD STV 20E
6
Audio Interface Diagram
Adjustments / Safety Parts / Main Diagram / Power Supply / Power Supply (Sat Rec) / Audio Diagram / Tuning CPU / Audio Interface / Tuner & RF (Sat Rec)