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5 - 1
SECTION 5 ADJUSTMENT PROCEDURES
5-1 PREPARATION
Almost adjustments must be adjusted on the adjustment mode. The shorten plug (see below) is required when entering the
adjustment mode.
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REQUIRED TEST EQUIPMENT
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ENTERING THE ADJUSTMENT MODE
q
Connect the shorten plug to the [SP] jack.
w
Push and hold
[8 SET]
,
[MR S.MW]
,
[BAND]
and
[MAIN/SUB]
keys, and then turn power ON.
NOTE:
Entering adjustment mode, keep on entering adjustment mode until dis-connect the shorten plug and turn power OFF.
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OPERATION ON THE ADJUSTMENT MODE
Change the adjustment channel or item [UP]
:
[MR S.MW]
key
Change the adjustment channel or item [DOWN]
:
[SCOPE]
key
Change the adjustment value
:
[R-DIAL]
While entering adjustment mode, some adjustments must push
[• LOCK]
or
[8 SET]
keys to write the adjustment value to the
CPU. Refer to following list in detail.
KEY
[• LOCK]
[8 SET]
OPERATION
Write the REFERENCE FREQUENCY ADJUSTMENT value.
Write the BFO ADJUSTMENT value.
Write the AFC ADJUSTMENT value.
Write the TRACKING ADJUSTMENT value.
Write the S-METER ADJUSTMENT value.
EQUIPMENT
DC power supply
Frequency counter
GRADE AND RANGE
Output voltage
: 6.0 V DC
Current capacity
: 1 A or more
Frequency range
: 0.1–1000 MHz
Frequency accuracy : ±1 ppm or better
Sensitivity
: 100 mV or better
EQUIPMENT
Digital multimeter
Standard signal
generator (SSG)
GRADE AND RANGE
Input impedance
: 10 k
Ω
/V DC or better
Frequency range
: 0.1–3000 MHz
Output level
: 0.1 µV–32 mV
(–127 to –17 dBm)
IC-R20
to [DC]
jack
to [SP] jack
3.5(d) mm
GND
I/O
to the antenna connector
Standard signal generator
0.1 V to 32 mV
( 127 dBm to 17 dBm)
Power supply
6 V / 1 A
JIG
3-conductor 3.5(d) mm
plug must be used.
Shorten I/O and GND line.
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CONNECTIONS