Pioneer SX-1080 Service Manual

SX-1 080
9.3 FMMPX
■ Connect as shown in Fig. 12, and set the FUNC¬
TION switch to “FM” and the MUTING switch
to “OFF”.
1. Set the FM signal generator to 98MHz un¬
modulated, 66 dB output.
2. ConnecttheoutputoftheMPX SG PILOT OUT
terminal to the horizontal axis input terminal
of an oscilloscope and tuner ass’y terminal 13
to the vertical axis input.
3. Set the SX-1080 dial pointer to 98MHz and
adjust the FM signal generator so that the
tuning meter deflects to the center of the
scale.
4. Adjust VR 3 so that a Lissajous pattern is traced
on the oscilloscope (Fig, 13).
5. Modulate the MPX SG at L+R (IkHz) to
deviate the 67.5kHz pilot signal (19kHz)
7.5kHz.
6 . Adjust Ts for minimum L channel or R channel
distortion. (However, within ±90% of the core
adjustment range).
7. Make the MPX SG main signal L or R and adjust
VR 4 for best separation.
8 . Next, set the MPX SG to 7.5kHz by pilot signal
(19kHz).
9. Adjust VRs for minimum output.
Fig. 13 Lissajous pattern
25

Pioneer SX-1080 Specifications

General

Total Harmonic Distortion	0.1% (at rated power)
Tuning Range	FM, MW
Damping Factor	30
Input Sensitivity	2.5mV (MM), 150mV (line)
Output	150mV (line), 1V (Pre out)
Speaker Load Impedance	4Ω to 16Ω
Frequency Response	5Hz to 100kHz
Signal to Noise Ratio	90dB (line)
Semiconductors	4 x FET, 6 x IC
Power Output	120 watts per channel (8 ohms, 20Hz-20kHz)