Operating instructions

6.1.2.1 Reproduce Head Azimuth
Reproduce Head Azimuth adjustment should be performed before Record
Head Azimuth adjustment.
1. Place a test tape on the transport and connect a dual-trace oscilloscope
to the outputs for CH 2 and CH 23 (or CH 2 and CH 15 on the 16 track
head assembly, CH 2 and CH 7 on the 8 track head assembly).
2. Set the Transport to All Repro mode on the Remote Control Unit.
3. Play the segment of the test tape containing the 8 kHz tone for coarse
adjustment.
4. Using an allen wrench, adjust the repro head for maximum phase
coherence of the two traces. The head may be tilted by loosening the
azimuth adjustment screw on the left (or right) and tightening the
azimuth adjustment screw on the right (left) an equivalent amount.
5. For fine adjustments, play the segment of the test tape containing the 16
kHz tone and carefully adjust the tilt of the head again as required for
maximum phase coherence of the two traces.
6.1.2.2 Record Head Azimuth
1. Thread a test tape on the transport; a dual-trace oscilloscope should be
connected to the CH 2 and CH 23 outputs on the MTR-90III (or CH 2 and
CH 15 on the 16 track head assembly, CH 2 and CH 7 on the 8 track head
assembly).
2. Set the Transport to All Sync mode on the Remote Control Unit.
3. Repeat § 6.1.2.1 Steps 3 through 5, adjusting only the Record Head.
MTR-90III Operation and Maintenance Manual
October 1990
Section 6 Alignment
6 - 5