Revox B261 Serviceanleitung Seite 47

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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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