Service manual

NOTE
Repeat paragraphs 4.2.7 and 4.2.8 several
times as the adjustments interact, i.e., each
time the scale is reset, the high frequency
will go off frequency and vice versa. The
process converges quickly so that both
adjustments can be accurately set.
e) Set A/B MIX control to vertical so that
the pitch of oscillators A and B may be compared.
4.2.12 OSCILLATOR B SCALE (Minitmoog Only)
1 OCT tab switch up
2 OCT tab switch down
"B" PITCH control full CCW
4.2.9 OSCILLATOR A OCTAVE TRANSPOSITION
1 OCT tab switch down
2 OCT tab switch down
a) Adjust REF frequency for zero beat with
oscillator A (Synthesizer =* 117 Hz, 2 octaves below
REF frequency).
b) Place 1 OCT tab switch up and zero beat
oscillator A with REF frequency using octave 1
adjust trimpot RIO (Figure 4-3, Synthesizer =* 233 Hz,
1 octave below REF frequency).
c) Place 2 OCT tab switch up and 1 OCT tab
switch
down and zero beat oscillator A with the REF
frequency using octave 2 adjust trimpot R21 (Figure
4-3, Synthesizer =* 466 Hz, unison with REF frequency).
4.2.10 OSCILLATOR A RANGE
a) Zero beat oscillator B with oscillator A using
range trimpot R504, Figure 4-5 (oscillator B will be
1 octave lower than oscillator A).
b) Hold down highest Bj, key and zero beat
oscillator B with oscillator A using scale trimpot
R529, Figure 4-5 (oscillator B one octave below
oscillator A).
1 OCT tab switch down
2 OCT tab switch up
REF frequency exactly 466 Hz
M
X
zz
N
YY
L
K
J
P
R510 .
OCTAVE
R504
RANGE
R529
SCALE
R511
HI END
a) Set range trimpot R16 (Figure 4-3) so that
oscillator A zero beats with REF frequency
(Synthesizer = 466 Hz, unison with REF frequency).
4.2.11 PREPARATION FOR TRACKING OSCILLATOR B
TO OSCILLATOR A (Minitmoog Only)
a) Perform paragraphs 4.2.6 through 4.2.10 to
tune oscillator A before tuning oscillator B (located
on oscillator board No. 5).
b) Disconnect jumper between collector and base
ofQ3.
c) Hold down lowest Bj, key using a wedge.
d) Turn off REF source since oscillator B
will be tuned by making it track oscillator A.
FIGURE 4-5 OSCILLATOR B TRIMPOT LOCATIONS
(BOARD NO. 5)
4.2.13 OSCILLATOR B HIGH FREQUENCY
COMPENSATION (Minitmoog Only)
1 OCT tab switch up
2 OCT tab switch up
"B" PITCH control vertical (in deadband)
a) Zero beat oscillator B with oscillator A using
range trimpot R504, Figure 4-5 (oscillators A and B
in unison).
b) Hold down highest Bb key and zero beat
oscillator B with oscillator A using high end trimpot
R511, Figure 4-5 (oscillators A and B in unison).
Repeat steps a and b several times.
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