ADJUSTMENT OF THE TPAE TRANSPORTING SECTION. (CONTINUED)

A. Adjustment of the S/T GUIDE ROLLER

a.Check the Playing back with a T-120 TAPE.

b.Make sure that excessive tape wrinkle does not occure at eatch S.T GUIDE ROLLER.

c.If tape wrinkle is observed at the S/T GUIDE ROLLER, turn the guide roller screw until there is not tape wrinkle.

B. Adjustment of the AC HEAD ASS’Y(TILT)

a.Play back a T-120 TAPE and check the running status of lower side of GUIDE POST.

b.If there is any problem, Turn the AC HEAD TILT SCREW until the running status improved (Fig. 5.2)

FIg.5.2 Adjustment of the AC HEAD ASS’Y

C. Adjustment of the AC HEAD Height(Fig. 5.3)

a.Play back T-120 TAPE.

b.Make sure that the gap between the lower end of AC head is 0.25m.

c.If the measurement of the gap is different from the refer- ence value 0.25m, turn the screw !,#until the desired gap is obtained.

FIg.5.3 Adjustment of X-POSITION

D. Adjustment of the AUDIO AZIMUTH(Fig. 5.4)

a.Play back the ALIGNMENT TAPE (DN2 : SP, NTSC,7KHz)

b.Check the AUDIO output with a AUDIO LEVEL METER.

c.Turn the AC HEAD AZIMUTH SCREW @until the maximum AUDIO output(-9dBm ~ -3dBm)is obtained.

FIg.5.4 Adjustment of AUDIO AZIMUTH, X-POSITION

E. Adjustment of the X-POSITION(Fig. 5.4 5.5)

a.Connect the PATH ADJ. FIXTURE to the PT01 on the

MAIN CIRCUIT BOARD.

b.Play back theALIGNMENT TAPE (DN2 : SP MONOSCOPE).

c.Connect the S/W pin and ENVE pin of the PATH ADJ. FIXTURE with the SCOPE PROBE.

d.Insert the adjustment bar in the AC HEAD ADJUST hole $and adjust the X-POSITION of the AC HEAD ASS’Y until the ENVE is maximum when the VR is on the CEN- TER.

*Three is the possibility that an another TRACKING CEN- TER can be occur when the AC HEAD ASS’Y turned completely in the counterclockwise direction, Hence adjust the X-position with AC HEAD ASS’Y adhering closely to the right side until the maximum ENVE is obtained.

e.The adjustment of the X-POSITION finished, check if the AUDIO LEVEL is degraded, then readjustment of the AUDIO AZIMUTH is required.

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

 

 

AC HEAD ADJUST HOLE

ADJUSTMENT BAR

 

 

 

 

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Daewoo VCR MECHANISM UNIT service manual Adjustment of the S/T Guide Roller, Adjustment of the AC Head ASS’YTILT