Dual Studio Concept CT 7040 Serviceanleitung Seite 3

Tuning instructions for CT 7040
Signal source Equipment
setting
Signal source setting Connection of
measuring instrument
Item tobe tuned Tuning, Remarks
FM oscillator
108 MHz L10 8.3 V DC ± 0.2 V
87.5 MHz Check: 2.0 - 2.5V
FM IF, Input circult
FM signal generator to
75-ohm
antenna input
Frequency
without
transmitters
approx. 98 MHz
0 - 1 mV,
Shift ± 40 kHz
Mod. 1 kHz
Tune to approx. 98 MHz
Harmonic detector
oscilloscope to
AF output
T 101
AF maximum
T 102
T 103 AF and harmonic distortion
minimum
90 MHz
Tune to approx. 90 MHz L 1/L 2, L 3/L 4, L 5
AF maximum
105 MHz
Tune to approx. 105 MHz TC 1, TC 2, TC 3
Repeat input-circuittuning
FM IF (fine tunIng)
Antenna to
75-ohm
antenna input
Receive strong
FM transmitter
at its nominal
frequency
DC voltmeter to: '
TP 2 - TP 3
T 103
Determine DC maximum
and DC minimum
T 103
Adjust power mean
T102 0V±1 mVDC
Repeat tuning
Pilot frequency 76 kHz, channel Separation
FM signal generator to
75-ohm
antenna input
Frequency with-
out transmitters
approx. 98 MHz
Tune to approx. 98 MHz,
Shift ± 40 kHz,
Mod. 1 kHz, 1 -2 mV,
without pilot tone
Frequency counter
to TP 5 VR 301
76 kHz ± 50 Hz
with 19-kHz pilot AF voltmeter,
oscilloscope to
AF output
VR 302 Maximum channel separation
Suppresslon of residua pilot frequencles (19 kHz)
FM signal generator to
75-ohm
antenna input
Frequency with-
out transmitters
approx. 98 MHz
Frequency without
transmitters
Tune to approx. 98 MHz
1 -2 mV, 19-kHz pilot
ON
AF voltmeter,
oscilloscope to
AF output
T 302 (lett channel) Minimum
T 301 (right channel)
Search threshold
FM signal generator to
75-ohm
antenna input
Frequency with-
out transmitters
approx. 98 MHz
Tune to approx. 98 MHz,
Shift ± 40 kHz,
Mod. 1 kHz
10 µV
Check the display VR 101 > i Display must light up
AM oscillator
520 kHz
DC voltmeter to
TP 1
T 201 0.65V DC ± 0.05V
1619 kHz
TC 203
9.0 V DC ± 0.4 V
150 kHz T202 1.6 V DC± 0.1 V
283 kHz TC 204 5.4 V DC± 0.4 V
AM IF, Input circuit
AM signal generator to
75-ohm
antenna input
999 kHz 20 µV - 1 mV, 1 kHz
Mod. 30%
999 kHz
T 203, T 204
Maximum
594 kHz
594 kHz AM ferrite-rod
antenna
1404 kHz
1404 kHz
TC 201
162 kHz 162 kHz LW ferrite-rod
antenna
252 kHz 252 kHz TC 202
(R 501 for display brightness)
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