TOSHIBA MV20FM4
Service Manual

ELECTRICAL ADJUSTMENTS
2-3: RF AGC 1. Receive the VHF HIGH (63dB). 2. Connect the digital voltmeter between the pin 5 of CP602 and the pin 1 (GND) of CP602. 3. Activate the adjustment mode display of Fig. 1-1 and press the channel button (02) on the remote control to select "RF AGC". 4. Press the VOL. UP/DOWN button on the remote control until the digital voltmeter is 2.5 ± 0.05V. 2-4: STEREO SEPARATION Please do the method (1) or method (2) adjustment. Method (1) 1. Set the multi-sound signal generator for each different L-ch and R-ch frequency (Ex. L-ch=2KHz, R-ch=400Hz) 2. 3. 4. and receive the RF. Connect the oscilloscope to the Audio Out Jack. Press the AUDIO SELECT button on the remote control to set to the stereo mode. Activate the adjustment mode display of Fig. 1-1 and press the channel button (18) on the remote control to select �FM LEVEL�. Press the VOL. UP/DOWN button on the remote control to adjust it until the audio output wave becomes a fine sine wave. 2-6: CUT OFF 1. Adjust the unit to the following settings. R CUT OFF=128, G CUT OFF=128, B CUT OFF=128, R DRIVE=64, B DRIVE=64, BRIGHTNESS=100, CONTRAST=85 2. Place the set with Aging Test for more than 15 minutes. 3. Set condition is AV MODE without signal. 4. Using the remote control, set the brightness and contrast to normal position. 5. Activate the adjustment mode display of Fig. 1-1 and press the channel button (01) on the remote control to select "CUT OFF". 6. Adjust the Screen Volume until a dim raster is obtained. 2-7: WHITE BALANCE NOTE: Adjust after performing CUT OFF adjustment. 1. Place the set with Aging Test for more than 15 minutes. 2. Receive the gray scale pattern from the Pattern Generator. 3. Using the remote control, set the brightness and contrast to normal position. 4. Activate the adjustment mode display of Fig. 1-1 and press the channel button (10) on the remote control to select "R CUT OFF". 5. Press the CH. UP/DOWN button on the remote control to select the "R CUT OFF", "G CUT OFF", "B CUT OFF", "R DRIVE" or "G DRIVE". 6. Adjust the VOL. UP/DOWN button on the remote control to whiten the R CUT OFF, G CUT OFF, B CUT OFF, R DRIVE, and G DRIVE at each step tone sections equally. 7. Perform the above adjustments 5 and 6 until the white color is looked like a white. 2-8: FOCUS 1. Receive the monoscope pattern. 2. Using the remote control, set the brightness and contrast to normal position. 3. Turn the Focus Volume fully counterclockwise once. 4. Adjust the Focus Volume until picture is distinct. 2-9: HORIZONTAL PHASE 1. Receive the monoscope pattern. 2. Using the remote control, set the brightness and contrast to normal position. 3. Activate the adjustment mode display of Fig. 1-1 and press the channel button (05) on the remote control to select "H PHASE". 4. Press the VOL. UP/DOWN button on the remote control until the SHIFT quantity of the OVER SCAN on right and left becomes minimum. 2-10: VERTICAL SHIFT 1. Receive the monoscope pattern. 2. Using the remote control, set the brightness and contrast to normal position. 3. Activate the adjustment mode display of Fig. 1-1 and press the channel button (07) on the remote control to select "V SHIFT". 4. Check if the step No. V. SHIFT is "0". 5. Adjust the VR401 until the horizontal line becomes fit to the notch of the shadow mask.

5.

Method (2) 1. Set the multi-sound signal generator L-ch=1KHz, R-ch =Non input and receive the RF. 2. Connect the oscilloscope to the Audio Out Jack (R-ch). 3. Press the AUDIO SELECT button on the remote control to set to the stereo mode. 4. Activate the adjustment mode display of Fig. 1-1 and press the channel button (18) on the remote control to select �FM LEVEL�. 5. Press the VOL. UP/DOWN button on the remote control to adjust it until the R-ch output becomes minimum. 6. Set the multi-sound signal generator L-ch=Non input, R-ch=1KHz and receive the RF. 7. Connect the oscilloscope to the Audio Out Jack (L-ch). 8. Press the AUDIO SELECT button on the remote control to set to the stereo mode. 9. Activate the adjustment mode display of Fig. 1-1 and press the channel button (18) on the remote control to select �FM LEVEL�. 10. Press the VOL. UP/DOWN button on the remote control to adjust it until the L-ch output becomes minimum.

(TV SECTION)
2-5: CONSTANT VOLTAGE 1. Connect the digital voltmeter to the TP501 (R502). 2. Set condition is AV MODE without signal. 3. Using the remote control, set the brightness and contrast to normal position. 4. Adjust the VR502 until the digital voltmeter is 115 ± 0.5V.

D3-2