MAGNAVOX MK125
Manual de Servicio

1-A. Preliminary/Final Checking and Alignment of Tape Path
Purpose: To make sure that the tape path is well stabilized. Symptom of Misalignment: If the tape path is unstable, the tape will be damaged. Note: Do not use an Alignment Tape for this procedure. If the unit is not correctly aligned, the tape may be damaged. 1. Playback a blank cassette tape and check to see that the tape runs without creasing at Guide Rollers [2] and [3], and at points A and B on the lead surface. (Refer to Fig. M3 and M4.) 2. If creasing is apparent, align the height of the guide rollers by turning the top of Guide Rollers [2] and [3] with a Guide Roller Adj. Screwdriver. (Refer to Fig. M3 and M5.)
Guide Roller [2] Guide Roller [3]

3. Check to see that the tape runs without creasing at Take-up Guide Post [4] or without snaking between Guide Roller [3] and ACE Head. (Fig. M3 and M5) 4. If creasing or snaking is apparent, adjust the Tilt Adj. Screw of the ACE Head. (Fig. M6)

Azimuth Adj. Screw

ACE Head Flat Screwdriver

Tilt Adj. Screw

Fig. M6

1-B. X Value Alignment
Purpose: To obtain maximum PB FM envelope signal at the preset position of the Tracking Control Circuit, align the Horizontal Position of the ACE Head. Symptom of Misalignment: If the Horizontal Position of the ACE Head is not properly aligned, maximum PB FM envelope cannot be obtained at the preset position of the Tracking Control Circuit. 1. Connect the oscilloscope to TP (C-PB and CTL) on the Main CBA. Use TP (RF-SW) as a trigger. 2. Playback the Gray Scale of the Alignment Tape (FL8N --- 2 head model, FL8NW --- 4 head model) and confirm that the PB FM signal is present. 3. Set the Tracking Control Circuit to the preset position by pressing CH UP button on the remote control unit then �PLAY� button on the unit. (Refer to note on bottom of page 2-3-4.)

ACE Head

A

B Take-up Guide Post [4]

Fig. M3

Lead Surface of Cylinder

Tape

Fig. M4

4. Use the Flat Screwdriver so that the PB FM signal at TP (C-PB) is maximum. (Fig. M6)

Correct
Guide Roller Tape

Incorrect

Tape

Take-up Guide Post

Fig. M5

2-3-3

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