Sony HMK-70 - Page 11

3-3. FM STEREO SEPARATION ADJUSTMENT
Test Setup:
HM K-70
fm | © re ©)
signal FM_ REC OUT
generator | ANT ie
: rd (Oa De
FUNCTION SW: FM STEREO
FM Stereo Signal Generator Setting:
Carrier frequency ...........0. 98 MHz
Output level ws 1,000 nV (60 dB)
MOd6 © ssctelsdeoestscesiiorigss yes Stereo
Audio (400 Hz) Mod ............ 67.5 kHz (90 %)
Pilot (19 kHz) Mod .............. 7.5 kHz (10%)
Procedure:
1. Set the signal generator input selector to the
left.
2. Tune the receiver to 98 MHz.
3. Adjust for maximum output on the
VTVM at the left channel, and record the out-
put level.
4. Record the residual signal level when the stereo
signal generator input selector is to the right.
Note: The output level to residual-level ratio
represents the separation.
t the right channel
Measure the separati
6. Readjust for minimum difference bet
ween left and right channel separation.
3-4. A-M I-F ALIGNMENT
Note: The a-m i-f transformers (CFU101 and
IFT101) are shipped from the factory
with all adjustments set for correct
operation. Therefore no adjustment is
required in the field service.
VTVM
MW FREQUENCY COVERAGE
Fig. 3-7. Adjustment parts location -
mmmesemmd §=145 kHz (modulated)
3-5. MW/LW FREQUENCY COVERAGE AND
TRACKING ALIGNMENT
Test Setup: een
a nna
VTVM
HMK-70
Oo
REC OUT | |
generator
ete)
Adjust for maximum
reading.
MW TRACKING
=) 600 kHz (modulated)
peewee | 400 kHz (modulated)
LW FREQUENCY COVERAGE
ae 145 kHz (modulated)
365 kHz (modulated) emEe
LW TRACKING
i
ssmmmesmed 320 kHz (modulated)
3-6. EXTERNAL ANTENNA COIL ALIGNMENT
Test Setup:
LW dummy
antenna HMK-70
am
signal
generator
Adjust for maximum
reading.
302.
120PF
3202 400P