Transmitter Adjustment - Icom IC-821H Service Manual

Vhf/uhf all mode
Table of Contents

Advertisement

5-5 TRANSMITTER ADJUSTMENT
MEASUREMENT
ADJUSTMENT
ADJUSTMENT
ADJUSTMENT CONDITIONS
VALUE
POINT
UNIT
LOCATION
UNIT
ADJUST
UHF
1
• MAIN band freq.
: 440.000 MHz
RF-B
Connect an
Adjust as follows:
RF-B
L36. L37.
HELICAL
• Connect a sweep generator to J7 on the
oscilloscope to J3
I
C32,C37
FILTER
RF-B unit and set as:
through a ditector.
Jax.
J.l
Sweep level
:71 mV
m.
(-10 dBm)
I
Center freq.
: 440.000 MHz
I
Sweep bandwidth
: 50 MHz
• Unplug Jl on the RF-B unit.
• Connect an oscilloscope through a
fJ
1
detector to J3.
7
fo
• Transmitting
Symmertrical
waves
UHF TOTAL
1
• MAIN band freq.
: Any
MAIN Connect an RF
Maximum level
MAIN
L1, L2
GAIN
• Mode
: USB
voltmeter to Jl or J2.
• [MIC GAIN]
: Center position
• Connect an audio generator to the
microphone connector and set as:
f--
1.5 kHz
f
2 mV
2
• Transmitting
18 mV (-22 dBm)
R2
3
• MAIN band freq.
Rear
Connect an RF power
Maximum level
RF-B
Adjust in
[EUR] version
435.00000 MHz
panel
meter to the [UHF ANn
repeatedly
[USA], [AUS] versions 440.00000 MHz
connector.
L1. L2. L3.
• Mode
:USB
L4, LS
• [MIC GAIN]
: Center position
• Connect an audio generator to the
microphone connector and set as:
1.5 kHz /2 mV
f--
• Grounds J23 on the MAIN unit.
4
• Transmitting
16W
R3
VHF TOTAL
1
• MAIN band freq.
Rear
Connect an RF power
Maximum level
RF-A
Adjust in
GAIN
[EUR] version
145.00000 MHz
panel meter to the [VHF ANn
repeatedly
[USA]. [AUS) versions 146.00000 MHz
connector.
L1. L2. L3.
• Mode
: USB
L4, LS,
• [MIC GAIN]
: Center position
C27. C3S,
• Connect an audio generator to the
Cl0l, Cl03
microphone connector and set as:
1.5 kHz / 2 mV
-
• Grounds J23 on the MAIN unit.
2
• Transmitting
l8W
R3
VHF
1
• MAIN band freq.
Rear
Connect an RF power
4SW
MAIN
R72
OUTPUT
[EUR] version
146.00000 MHz
pan Ie meter to the [VHF ANn
POWER
[USA]. [AUS] versions 148.00000 MHz
connector.
• Mode
:FM
• [RFPWRJ
: Max. level
• Transmitting
2
• [RF PWR]
: Minimum level
Less than 6W
Verify
• Transmitting
3
• Mode
: USB
3SW
Rl0S
• Connect an audio generator to the
mocrophone connector and set as;
1.5 kHz /20 mV
• [MIC GAIN]
: Center position
• [RF PWR]
: Max. level
• Transmitting
5-8

Advertisement

Table of Contents
loading

Table of Contents