Icom IC-T81A, Service Manual

Page: 15 / 53

5 - 1
AD-92SMA
Optional SMA–BNC adaptor
1/8" (3.5 mm)
3-conductor plug
68 k
Ω
-
+
to [SP] jack
Audio generator
AC millivoltmeter
Power supply
13.5 V / 3 A
to [MIC] jack
FM Deviation
meter Attenuator
40 dB or 50 dB
RF power meter
10 W/50
Ω
Frequency
counter
Standard signal
generator
CAUTION:
to the antenna connector
DO NOT transmit while
an SSG is connected to
the antenna connector.
JIG
5-1 PREPARATION
‘ ‘ REQUIRED TEST EQUIPMENT
‘ ‘ ENTERING THE ADJUSTMENT MODE
q
Connect a 68 k
Ω
terminator to the [SP] jack.
w
Push and hold the [SQL] key, and then turn power ON.
Note: The frequency of wide range appears at the display using this operation.
■
CONNECTION
EQUIPMENT
DC power supply
RF power meter
(terminated type)
Frequency counter
FM deviation meter
GRADE AND RANGE
Output voltage : 13.5 V DC
Current capacity : 3 A or more
Measuring range : 1–10 W
Frequency range : 28–1500 MHz
Impedance : 50
Ω
SWR : Less than 1.2 : 1
Frequency range : 0.1–1500 MHz
Frequency accuracy : ±1 ppm or better
Sensitivity
: 100 mV or better
Frequency range : 30–1500 MHz
Measuring range : 0 to ±10 kHz
EQUIPMENT
DC voltmeter
Audio generator
Standard signal
generator (SSG)
Oscilloscope
AC millivoltmeter
Attenuator
GRADE AND RANGE
Input impedance : 50 k
Ω
/V DC or better
Frequency range : 300–3000 Hz
Measuring range : 1–500 mV
Frequency range : 28–1300 MHz
Output level : 0.1 µV–32 mV
(–127 to –17 dBm)
Frequency range : DC–20 MHz
Measuring range : 0.01–20 V
Measuring range : 10 mV–10 V
Power attenuation : 40 or 50 dB
SECTION 5 ADJUSTMENT PROCEDURES