amstrad stv 2100n free download

File name Am2100N.pdf

AMSTRAD STV 2100 N Adjustments Test Equipment: VIF Sweep Generator; SIF Sweep Generator; Colour Bar/Dot/Cross Hatch Generator; DC Power Supply (14V); Oscilloscope; Vacuum Tube Voltmeter; Volt Ohmmeter; High Voltage Meter; Ampere Meter (0.5 Class, DC 3mA Max.) Demagnetizing Coil; Philips Pattern Generator; Frequency Counter; Continuous Waveform Generator. (See TV Section Table opposite). COLOUR PURITY ADJUSTMENT (SEE FIG.7) BEFORE ALL ADJUSTMENT DESCRIBED BELOW ARE ATTEMPTED, V-HOLD, H-HOLD, V-HIGH, B+ VOLTAGE AND FOCUSING ADJUSTMENT MUST BE COMPLETED. SAT SECTION 1 CONVERGENCE ADJUSTMENT (SEE FIG.7) 1. Receive a dotted pattern. 2. Unfix the convergence magnet damper and align red with blue dots at the center of the screen by rotating (R,B) static conver gence magnets. 3. Align Red/Blue with green dots at the center of the screen by rotating (RB-G) static convergence magnet. 4. Fix the convergence magnets by turning the damper. 5. Remove the DY wedges and slightly tilt the deflection yoke horizontally and vertically to obtain the good overall covergence. 6. Fix the deflection yoke by wedges. 7. If purity error is found, follow "PURITY ADJUSTMENT" instructions. TV SECTION STEP 1). FUNCTION Tank Coil Adjustment. SIGNAL IN VIF Signal Generator. Tuner Test point Tp & tuner case (Earth). SIGNAL OUT Oscilloscope TP601 & Earth. METHOD Adjust AGC bias voltage for maximum amplitude of waveform. Adjust the output level of VIF sweep Generator to achieve 2Vp-p output on oscilloscope. Adjust T103 to obtain maximum amplitude of response at PC (39.5 MHz). Connect resistor 100 Ohm between TP102 & TP103. Adjust AGC bias voltage for maximum amplitude of waveform. Adjust the level of sweep Genetator to achieve 2Vp-p output Increase the output level of sweep generator in 20dB. Adjust AGC bias voltage to achievf 2Vp-p output Adjust tuner connvert for coil to ortain the waveform shown. Adjust the output level of VIF Signal Generator. for maximum amplitude waveform without saturation, adjust Ti 02 to obtain frequency response as shown in the fig., at 39.5MHz. Connect the TP101 (AGC) to Earth. Set the frequency of FM signal generator 6MHz with 400Hz 25KHz deviation and signal output level to 100dB. Adjust T105 to obtain the maximum output. Connect Voltmeter to TP405 and Earth. Adjust VR901 to read DC 106.5V ± 0.5V. Set the TV to AV mode, connect the Frequency counter between IC302 Pin 41 and Earth. Adjust VR303 (H.FREQ.) to the reading 15330 ± 30Hz. and back to TV mode. Receive Monoscope Pattern, adjust VR301 (H.CEN) con trol to obtain a normal picture. Set the TV to AV mode, connect the Frequency counter between V-Deflection York and Earth, adjust VR304 (VHOLD) to the reading 44Hz + 2-0 Hz, and back to TV mode. Receive Monoscope Pattern, adjust VR401 (V-HIGH) con trol to obtain a normal picture. Set screen control to min.turn R.G.B. VR501, 502, 503 and dry. VR504, 505 to mid. position. Turn the Sub-Brightness (VR305) control to mid. position, then set the Contrast cont