Operating instructions

2.1 Inspection
Before making any electrical connections, the equipment should be inspected
visually. If there is any evidence of damage due to rough handling in
shipping, it is the responsibility of the customer to notify the carrier and
submit a claim. Do not connect or attempt to use the MTR-90III or
accessories until this inspection has been made.
1. Inspect the equipment for any parts which may have become loose or
damaged during shipping.
2. Check the plug-in PCB Assemblies in the card cages:
A. Grasp the top of each door in the front of the MTR-90III and pull to
open.
CAUTION! The edges of the doors are very sharp.
B. The upper card cage should contain the proper quantity of Audio
boards (i.e., 8, 16 or 24). Eight and sixteen track versions of the
MTR-90III will have no cards in slots 9–24 or 17–24 respectively.
C. The lower card cage should contain the POWER SUPPLY PCB
Assembly and PCB Assemblies numbered 1–7 installed in the
correspondingly numbered card slots.
#1 REEL CONTROL PCB Assembly #5 I/O CONTROL PCB Assembly
#2 CAPSTAN CONTROL PCB Assembly #6 TAPE COUNTER PCB Assembly
#3 TRANSPORT CONTROL PCB Assembly #7 BIAS PCB Assembly
#4 MASTER CPU PCB Assembly
D. Remove the TRANSPORT CONTROL PCB Assembly (#3) and
examine DIP switch SW1 (Figure 2-1).
SW1-2 and SW1-3 have been set to the ON position at the factory.
These switches are for selecting Stand-by mode. Stand-by mode
automatically switches the Output Monitor to Input mode when the
following conditions are met: the tape is in Stop or Fast Wind mode,
the READY/SAFE switches have been set to the READY position and
either the ALL REPRO or ALL SEL·REP button on the Remote
Control Unit has been pressed. This mode is called "Stop Stand-by"
when entered from the Stop mode and "Fast Stand-by" when entered
from Fast Wind modes. SW1-1 and SW1-4 have been set to the OFF
position at the factory. When the Master Audio Attenuation Switch
(SW4 on the BIAS CONTROL PCB Assembly) is off, audio output is
attenuated when the machine is in fast wind modes (see Figure 2-2
and Table 2-4). When SW1-1 on the TRANSPORT CONTROL PCB is
off, the Audio output will be attenuated when the CUE button (Lifter
Defeat) is pressed during Fast Wind modes. When SW1-1 is on, no
audio attenuation will take place when the lifters are defeated.
R126
O
N
O
N
1234
SW1
C90
Figure 2-1
SW1 on the TRANSPORT CONTROL PCA
Section 2 Installation
2 - 2
October 1990
MTR-90III Operation and Maintenance Manual