Dual CR 900 RC Serviceanleitung Seite 3

Tuning Instructions for CR 900 RC
Signal source Equipment Signal source setting Connection of Нет to be tuned Tuning, Remarks
setting measuring instrument
1) FM oscillator
87.5 MHz DC voltmeter L4 8.0 VDC + 0.2\
to TP 1 (В 402)
108 MHz Check approx. 1.6 V DC
2) FM IE input circuit
FM signal generator Frequency 0-1 тм Shift + Harmonic detector Ti AF maximum
to 75 ohm without 40 kHz, Mod. 1 kHz oscilloscope
antenna input transmitters Tune to approx. to AF output L 404
ворох 98 МНЕ МНЕ L405 AF and harmonic
approx. 90 MHz Tune to approx. RUM
90 MHz = SH п
aircoils Maximum
ра
3} FMIF (fine tuning)
Antenna to 75 ohm Receive strong DC voltmeter L405 Determine DC max. and DC min
antenna input FM transmitter to ТР 3-TP 4
at its nominal (over R 412) І-405 Adjust power mean
еу 1404 OVDC + 10 ту
Repeat tuning
4) Pilotfrequencies 76 kHz, Channel separation
FM Signal generator Frequency Tune to approx. 98 MHz Frequency counter VR 501 76 kHz + 50 Hz
to 75 ohm without Shift + 40 kHz, toTP5
antenna input transmitters Mod. 1 kHz {bridge 3 J 47)
approx. 98 MHz 1-2 mV, without pilot
Mono key: OFF with 19 kHz pilot AF voltmeter, VR 502 Maximum channel separation
oscilloscope
to AF output
5) Suppression of residual pilot frequencies (19 kHz)
FM signal generator Frequency Tune to approx. AF voltmeter, LPF (left channel) Minimum
to 75 ohm without 98 MHz, 1-2 mV oscilloscope
antenna input transmitters 19 kHz pilot ON to AF output
approx. 98 MHz LPF (nght channel)
6) FM Search threshold
FM signal generator Frequency with- Tune to approx. 98 MHz | Check the display VR 401 Goal A
to 75 ohm out transmitters Shift + 40 kHz, must light up
antenna input approx. 98 MHz Mod. 1 kHz, 10 ру
7) AMoscillator
AM 522 kHz DC voltmeter 1 402 16VDC + 01У
E to TP 1 (А 402) ік
АМ 1611 kHz ТС 402 84VDC+0.4V
Repeat tuning
8) АМ ІБ input circuit
AM signal generator 10 uV-1m\ 1 kHz AF voltmeter, Maximum
to AM antenna Mod. 30% oscilloscope
input 999 kHz 999 kHz to AF output L 403
603 kHz 603 kHz L 401
1404 kHz 1404 kHz TC 401
9) AM Search threshold
AM signal generator 100 ЫМ 1 kHz Check the display Signal РІ
to AM antenna 999 kHz Mod. 30% VR 402 must light up
input 999 kHz