Operating instructions

6.1.1.3 Reinstalling the Transport Deck Plate
Reinstall the Transport Deck Plate by installing the parts in the reverse order
of § 6.1.1.2.
❑ Make sure no loose parts, tools, wires, etc. have been left on the
Transport Deck Plate.
❑ When reinstalling the head assembly base, be sure not to scrape the
tacho roller or capstan roller with the edges of the base.
❑ To avoid stripped threads, do not overtighten the screws that secure the
swing arm guards collars.
NOTE: Before reinstalling the Transport Deck Plate, confirm that swing arm
travel, solenoid and spring tension adjustments have been completed. Refer
to § 6.1.3 through § 6.1.7.
6.1.2 Head Geometry
The MTR-90III record and reproduce heads are mounted to the head
assembly block via an ingenious system that permits a simple 2-screw
adjustment for azimuth (left-right tilt), without affecting the zenith (forward-
back tilt), wrap (penetration of the head into the tape path) or head height.
This system makes it possible for OTARI to factory set the zenith, wrap and
height so that no further field adjustments are required. The only adjustment
recommended is for azimuth, which maintains maximum phase coherency
across the various tracks of the heads and ensures optimum high frequency
response between the record and reproduce heads.
Refer to Figure 6-2 for the location of the azimuth adjustment screws.
Reproduce head azimuth must be checked and adjusted before record head
azimuth can be checked.
Figure 6-2
Record/Reproduce Head Azimuth Adjustment
AZIMUTH ADJUSTMENT SCREWS
PROPER
AZIMUTH
RIGHT TILT
RECORD
HEAD
REPRODUCE
HEAD
LEFT
TILT
Section 6 Alignment
6 - 4
October 1990
MTR-90III Operation and Maintenance Manual