Section 5 Adjustment Procedures; Preparation - Icom ic-r20 Service Manual

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.
' ' REQUIRED TEST EQUIPMENT
EQUIPMENT
Output voltage
DC power supply
Current capacity
Frequency range
Frequency counter Frequency accuracy : ±1 ppm or better
Sensitivity
' ' 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.
I OPERATION ON THE ADJUSTMENT MODE
Change the adjustment channel or item [UP]
Change the adjustment channel or item [DOWN]
Change the adjustment value
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.
' ' CONNECTIONS
Standard signal generator
0.1 V to 32 mV
( 127 dBm to 17 dBm)
GRADE AND RANGE
: 6.0 V DC
: 1 A or more
: 0.1–1000 MHz
: 100 mV or better
: [MR S.MW] key
: [SCOPE] key
: [R-DIAL]
KEY
Write the REFERENCE FREQUENCY ADJUSTMENT value.
[• LOCK] Write the BFO ADJUSTMENT value.
Write the AFC ADJUSTMENT value.
Write the TRACKING ADJUSTMENT value.
[8 SET]
Write the S-METER ADJUSTMENT value.
to the antenna connector
EQUIPMENT
Digital multimeter
Standard signal
generator (SSG)
OPERATION
3.5(d) mm
Power supply
to [DC]
6 V / 1 A
jack
IC-R20
5 - 1
GRADE AND RANGE
Input impedance : 10 kΩ/V DC or better
Frequency range : 0.1–3000 MHz
Output level : 0.1 µV–32 mV
(–127 to –17 dBm)
JIG
Shorten I/O and GND line.
I/O GND
3-conductor 3.5(d) mm
plug must be used.
to [SP] jack