Sony AV-3420CE Service Manual

CHOP position. Pull out the 5X magnifierand adjust HORIZONTAL POSITION toobserve the vertical blanking interval.6. Adjust the 25 PG coil so that the 50 PG pulseleads the VD pulse by 8 H+1H. See Fig. 44.ae of! 20.5 H (ae|flFig. 4-4.4-3-5. Playback Servo CheckTest Point:Check for:Adjustment:Signal source:TP-706Servo locks in center of pull-in range.NoneNoneEquipment Required:1. Video Alignment tape or prerecorded tape2. OscilloscopeProcedure:1. Connect scope to TP-706. Set up the 2V/cm,2ms/cm ranges.2. Thread the alignment tape.3. Set up the playback mode.4. Check to see that the PG pulse locks in thecenter of the trailing edge of the rectangularpulse. If not, perform Sec. 4-3. TV record modespeed adjustment. Check also that Q719, Q720emitter dc potential is between 3.5 V~4.5 Vdc.Fig. 4-5.4-3.