SYLVANIA SRDV495
Service Manual

1-D. Azimuth Alignment of Audio/Control/ Erase Head
Purpose: To correct the Azimuth alignment so that the Audio/ Control/Erase Head meets tape tracks properly. Symptom of Misalignment: If the position of the Audio/Control/Erase Head is not properly aligned, the Audio S/N Ratio or Frequency Response will be poor. 1. Connect the oscilloscope to the audio output jack on the rear side of the deck. 2. Playback the alignment tape (FL8NW) and confirm that the audio signal output level is 8kHz. 3. Adjust Azimuth Adj. Screw so that the output level on the AC Voltmeter or the waveform on the oscilloscope is at maximum. (Fig. M6) Note: Upon completion of the adjustment of Azimuth Adj. Screw, check the X Value by pushing the CH UP or DOWN buttons alternately, to check the symmetry of the envelope. Check the number of pushes to ensure preset position. The number of pushes CH UP button to achieve 1/2 level of envelope should match the number of pushes CH DOWN button from center. If required, redo the �X Value Alignment.�

2. When the tape has been curled up or bent, turn the alignment screw to adjust the height of REV Post. (Refer to Fig. M11 and M13.)

REV Post [5]

Take-up Guide Post [4]

Fig. M11

Correct
REV Post Tape

Incorrect

Tape

Take-up Guide Post

1-E. Checking and Alignment of Tape Path during reversing
Purpose: To make sure that the tape path is well stabilized during reversing. Symptom of Misalignment: If the tape path is unstable during reversing, 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. Insert a black cassette tape into the tray and set the unit to REV. Then confirm if the tape has been curled up or bent at the Take-up Guide Post[4] or REV Post[5]. (Refer to Fig. M11 and M12.)
Alignment Screw Tape Guide Assembly

Fig. M12

Fig. M13

2-3-5

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