Figure 3.
2. FM Adjustment
(1) The impedance of FM antenna terminal is 75½.
Therefore, connect coaxial cable (3C-2V etc.) between FM SG and antenna terminal when wiring.
(2) There are two kind in indication of FM SG output attenuator.
1) Attenuator with marking of 75½ openÉopen indication type.
2) Attenuator with marking of 75½ load or close É load or close indication type.
(3) FM SG output level in this FM adjustment are described as open indication type. The left table
shows relations among FM SG attenuator indication (dB), available power ratio (dBf) and antenna
terminal voltage (dB/µV) in each indication type.
Notes:
1. BAND Switch..................................................................................................................................FM
2. BALANCE .................................................................................................................................Center
3. TREBLE/BASS .........................................................................................................................Center
4. Connect as shown in figure 3.
5. Refer to figure 1~2 for Adjustment Points.
Item
FM SSG Available Antenna
Attenuator Power Terminal
Type
Indication Ratio Voltage
Open indication 0dB 5.2dBf 6 dB/µV
type 60dB 65.2dBf 66dB/µV
Load or close 0dB 11.2dBf 12dB/µV
indication type 54dB 65.2dBf 66dB/µV
STEP SUBJECT
FEED SIGNAL
MEASURE OUTPUT ADJUSTMENT ADJUST FOR
Discriminator
MPX
Adjustment
98MHz 60dB
22.5kHz Dev.
FM SSG
98MHz 60dB
75kHz Dev
FM SSG
ANT Jack
or
Point
Same as
above
Between Point & Point
(R111)
, DC Volt Meter.
Between Point ,
Frequency Counter
T101
VR301
1
2
DC 0V ±10mV
76kHz ± 50Hz
FROM TO