Revox B261

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8261 SA
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4/6
4.7
Adjusting the
decoder 1.726.760
Required test equipment
:
-
FM standard-signal
generator
-
Stereo
demodulator
-
Generator
Ri
50
ohms
-
AF
vol-tmeter
-
OsciLl-oscope
with externally triggerable
probe
I0:1
-
Frequency counter
L11 L9 MP15
L6
L5
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4.7.1-
Adjusting the 76 kHz oscillator
J1.5
from
the
Ic4
pin
10
)
counter
Feed
98.0
MHz,
approx. 2 mV EMF
without
pilot
tone
standard-signal
generator
(without
modulatron) into
antenna input.
Connect frequency counter
to test
point
MP12
(R43,
and adjust
L7 to 37.950 kHz.
Switch on
pilot
tone:
the
reading on the
frequency
should be 38 kHz.
4.7.2
Adjusting
the l-9
kHz
band-pass filter
-
Short
circuit RI
(
15 kohm) and connect
oscifl-oscope
with
probe
to test
point
MP13
(R2,/C3
)
.
-
Adjust
L2
(19
kHz band-pass filter) for maximurn
voltage
(approx.
110 mV AC) and remove
strap across
Rl.
-
Adjust Ll for minimum voltage.
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