Am Noise Canceler Adjustment - Pioneer FX-MG8057ZT/UC Service Manual

1

6.4 AM NOISE CANCELER ADJUSTMENT

A
- Connection Diagram
SSG
2-signal pad
Pulse generator
(equivalent to HP8011A)
- AM Noise Canceler Adjustment
Setting of the pulse generator (setting of
B
superimposed pulse)
50µs
5ms
1. Setting of SSG
Receiving frequency
Percentage modulation : 30%
C
Modulation frequency : 400 Hz
Antenna input
2. Set the system as shown in 1., then tune to a
radio station.
3. Superimpose the pulse over signal to set
modulation of SSG to OFF.
4. Use a noise meter to monitor output. Adjust
VR561 to minimize the noise level.
D
E
F
68
1
2
AM dummy
Head Unit
antenna
Pulse width :50µsec
4Vp-p(EMF)
Pulse intervals :5msec
Pulse voltage :4Vp-p
: 1,000 kHz
: 74 dBµV (EMF)
FX-MG8057ZT/UC
2
3
Output
Noise meter
3
4
4