Operating instructions

❑ VARI Mode: The capstan speed can be varied through a range of just
over ±20%, almost four musical steps, as set by the adjacent PITCH
CONTROL knob [2]. The speed variation is indicated on the Speed
Display screen [4] in percent or ips. The SPEED DISPLAY button [5]
must be pushed to view this variation. The speed is varied from the
speed set by the TAPE SPEED button (§3.1, [2]) on the MTR-90III.
❑ EXT Mode: The capstan speed can be varied by reference to an external
oscillator, synchronizer, etc.
[7] INDIVIDUAL Button When the INDIVIDUAL button is engaged, the 3-position Output Selector
Switches [8] independently determine the signal source for each of the
MTR-90III channel output amplifiers, VU meters, and output jacks unless the
channel is in Ready mode. The individual channel switches can be overridden
by the master ALL INPUT, ALL SEL·REP or ALL REPRO buttons.
[8] Output Selector Switches/Mode Indicators
These 3-position switches select the source for the output signal. The column
of 3 LEDs above each switch indicates the selected status.
❑ INPUT Mode: With the Output Selector switches set to the INPUT
position (lever up), the input electronics, not the tape, are monitored
whether the machine is in Stop, Play or Record mode. The amber
indicator (top row) for the channel illuminates.
❑ SEL·REP Mode: With the Output Selector switches set to the to the
SEL·REP position (lever centered), the channel output consists of the
tape playback picked up with the record head and amplified via the sync
amp for that channel. The green indicator (middle row) for the channel
illuminates.
❑ REPRO Mode: With the Output Selector switches set to REPRO position
(lever down), the output signal is playback driven from the reproduce
head and reproduce electronics. The corresponding amber indicator
(bottom row) should be illuminated.
[9] ALL INPUT/ALL SEL·REP/ALL REPRO Buttons
When switching all channels to one of the three possible modes, the master
ALL INPUT, ALL SEL·REP or ALL REPRO push buttons can be used instead
of the 24 Output Selector switches. These buttons override the individual
Output Selector Switches [8].
❑ All Input Mode: When the ALL INPUT button has been pressed, all of the
channels enter Input mode, and the amber indicator to the left and all 24
amber LEDs to the right of this button illuminate. See Table 3-1.
❑ All Sel·Rep Mode: When the ALL SEL·REP button has been pressed, all
of the channels are set into Sel·Rep mode, and the green indicator to the
left and the green LEDs to the right (middle row) or the amber LEDs (top
row) illuminate, depending on whether the machine is in Stop, Play or
Record mode and on the Ready/Safe status of the individual channels.
See Table 3-1.
❑ All Repro Mode: When the ALL REPRO button has been pressed, all of
the channels are set into Repro mode, and the amber indicator to the left
and the amber LEDs to the right (bottom row) or the amber LEDs (top
row) illuminate, depending, as in the case of the ALL SEL·REP button, on
whether the machine is in Stop, Play or Record mode and on the
Ready/Safe status of the individual channels. See Table 3-1.
Section 3 Controls and Indicators
3 - 8
October 1990
MTR-90III Operation and Maintenance Manual