Revox B261 Serviceanleitung Seite 43

STI'DtrR
]IEVOX
8261 SA
SECTION 4/2
4.2
Adiustinq the synthesizer
1.126.770
Test equipment required:
-
RF
voltmeter
- Digital vol-tmeter
Caution:
Do
not change the setting of the trimmer capacitor
C26!
Adjusting procedure: (Fine-tuning
vol,tage of varactors)
- Connect digital
voltmeter to test point
MP1
(Jl pin 2).
- Adjust the fine-tuning vol-tage for 87.5
MHz
(station
sefector
key 1) witn L2 so that the digital voltmeter
gives a reading
of 4.5 V +0.03
V-
- Adjust thä fine-tuni-ng
vol-tage for 108.00 l4Hz (station
key
5)
with C9 so that the digital voltmeter gives a reading of 24
V
+0.2 v.
Since there j.s mutual influence
in these adjustments, they
must
be repeated until the specified values are attained.
-
Connect
RF
voltmeter to test point
MP2
(white
stranded wire,
plug contact on I.726.730).
The measured
voltage
should
range
between 100 and 210
mV
for both frequencies (87.5
and
I08.0
MHz).
Adjust deviations with T1.
The
difference
between
the
measurements
at
87.5
MHz
and 108.0
MHz
should
not
exceed
l0
mV.
c18
L4 L5
c22
c32 L6 L8
c36
L2
Fig.4.3
L3
L1
Fig.4.2
MP2
L1O
L12
L14
L16
Ll3
L15 L17
L18