LG Electronics TL-AT130M Value Adjustment, Precise Adjustment Azimuth adjustment, 1KHZ 7KHZ

DECK MECHANISM ADJUSTMENT

5-2. Confirm that the tape passes smoothly between the Take-up Guide and Pinch Roller(using a mirror or the naked eye).

1)After completing Step 5-1.(Preliminary Adjustment), check that the tape passes around the Take-up Guide and Pinch Roller without folding or curling at the top or bottom.

(1)If folding or curling is observed at the bottom of the Take-up Guide then slowly turn the Tilt Adjustment Screw(C) in the clockwise direction.

(2)If folding or curling is observed at the top of it then slowly turn the Tilt Adjustment Screw(C) in the counterclockwise direction.

NOTE:

Check the RF envelope after adjusting the A/C Head, if the RF waveform differs from Fig. C-5-4, performs Precise Adjustment to flat the RF waveform.

5-3. Precise Adjustment (Azimuth adjustment)

Test Equipment/ Fixture	Connection Point	Test Conditions	Adjustment Point
		(Mechanism Condition)
• Oscilloscope	• Audio output jack	• Play an Alignment Tape	• Azimuth Adjustment Screw(A)
• Alignment Tape(SP)		1KHz, 7KHz Sections	• Height Adjustment Screw(B)

•Screw Driver(+) Type 5mm

Adjustment Procedure

1)Connect the probe of the oscilloscope to Audio Output Jack.

2)Alternately adjust the Azimuth Adjustment Screw(A) and the Tilt Adjustment Screw(C) for maximum output of the 1KHz and 7KHz segments, while maintaining the flattest envelope differential between the two frequencies.

1KHZ 7KHZ

A:Maximum B:Maximum

Fig. C-5-4

6. X-Value Adjustment

Purpose: To obtain compatibility with the other VCR(VCP) Models.

Test Equipment/ Fixture	Connection Point	Test Conditions		Adjustment Point
		(Mechanism Condition)
• Oscilloscope	• CH-1: PB RF Envelope	• Play an Alignment Tape		Groove at the
• Alignment Tape(SP only)	• CH-2: NTSC: SW 30Hz
			Left	Base A/C
• Screw Driver(+) Type 5mm	PAL: SW 25Hz
	• Head Switching Output
	Test Point			Right
	• RF Envelope Output Test
	Point

Adjustment Procedure	Adjustment Diagram
1) Release the Automatic Tracking to run long enough for	X-Value Adjustment Hole
tracking to complete it’s cycle.	Fixed Screw
2) Loosen the Fixed Mounting Screw and move the Base
Assembly A/C Head in the direction as shown in the dia-	Azimuth Adjustment	Tilt Adjustment Screw(C)
gram to find the center of the peak that allows for the max-
	Screw(A)
imum waveform envelope.
	Height Adjustment Screw(B)
This method should allow the 31µm Head to be centrally
located over the 58µm tape track.
3) Tighten the Base Assembly A/C Head mounting Screw.
	Connection Diagram	OSCILLOSCOPE
	RF ENVELOPE OUTPUT TEST POINT
	HEAD SWITCHING OUTPUT TEST POINT	CH-1 CH-2

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