Daewoo VCR MECHANISM UNIT Playback Phase ADJUSTMENTFig, Adjustment of the LINEARITYFig

ADJUSTMENT OF THE TPAE TRANSPORTING SECTION. (CONTINUED)

FIg.5.5 Adjustment of the X-POSITION

F. PLAYBACK PHASE ADJUSTMENT(Fig. 5.6)

Test Point	S/W PULSE TEST PIN	MAIN CIRCUTE BOARD
	ENVELOPE TEST PIN	MAIN CIRCUTE BOARD
Measurement Equipment	OSILLOSCOPE
Adjustment	VR 595(PG SHIFTER)	MAIN CIRCUTE BOARD

PHASE GENERATOR(PG) SHIFTER determine the VIDEO HEAD SWITCHING POINT when the TAPE is played back.

If an adjustment of the PHASE GENERATOR(PG) SHIFTER is not doneprecisely, There can be a HEAD SWITCHING NOISE or a VERTICAL JITTER problem, vibration of the picture on the screen, not good quality of picture in special play back.

a.Connect the PT01 on the MAIN CIRCUIT BOARD with a PATH ADJ. FIXTURE.

b.Play back an ALIGNMENT TAPE (DN-2 : MON- SCOPE).

c.Connect the S/W PULSE TEST PIN on the PATH ADJ.FIXTURE with a CHANNEL-1 SCOPE PROBE.

d.Connect the VIDEO OUT on the MAIN CIRCUIT BOARD with a CHANNEL-2 SCOPE PROBE(1V/div).

e.Control thePG VOLUME until the time interval between the SWITCHING PULSE and the V-SYNC SIGNAL is sithin the 6.5±0.5H as shown in fig. 5.6

Fig.5.6

G.Adjustment of the LINEARITY(Fig. 5.7)

Test Point	S/W PULSE TEST PIN	PATH ADJ. FIXTURE
	ENVELOPE TEST PIN	PATH ADJ.FIXTURE
Measurement Equipment	OSILLOSCOPE
Adjustment	VR CONTROL	PATH ADJ.FIXTURE
	S/T GHIDE ROLLER	TAPE TRANSMISSON SECTION

a.Connect the PT01 on the MAIN CIRCUIT BOARD with a

PATH ADJ.FIXTURE.

b.Play back an ALIGNMENT TAPE (DN-2 : MONOSCOPE Signal).

c.Connect the FIXTURE S/W PULSE TEST PIN on the

PATH ADJ. CHANNEL-1 SCOPE PROBE.

d.Connect the VIDEO OUT on the MAIN CIRCUIT BOARD with a CHANNEL-2 SCOPE PROBE.(1V/div).

e.Adjust the VR CONTROL on the ADJ. FIXTURE until the ENVELOPE signal is maximum while play back the

ALIGNMENET TAPE.

f.Adjust the S/T GUIDE ROLLER until the envelope signal waveforms of the entrance and exit sides are as shown in Fig. 5-7.

FIg.5.7 Adjustment of Linearity

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