Section 5 Adjustment Procedures; Pll And Transmitter Adjustment - Icom IC-T7H Service Manual

SECTION 5

5-1 PLL AND TRANSMITTER ADJUSTMENT

ADJUSTMENT ADJUSTMENT CONDITION
PLL LOCK 1 • Displayed frequency :
VOLTAGE 145.000 MHz
(VHF) • Receiving
2 • Transmitting
(UHF) 1 • Displayed frequency :
440.000 MHz
430.000 MHz
• Receiving
2 • Transmitting
PLL 1 • Displayed frequency :
REFERENCE 445.000 MHz
FREQUENCY 435.000 MHz
• Transmitting
OUTPUT 1 • Displayed frequency :
POWER 145.000 MHz
• Output power: High
• Transmitting
2 • Output power: Low
• Transmitting
3 • Displayed frequency :
445.000 MHz
435.000 MHz
• Output power: High
• Transmitting
4 • Output power: Low
• Transmitting
FM 1 • Displayed frequency :
145.000 MHz
DEVIATION
• Connect an audio generator to
the [MIC] connector and set as:
1 kHz/95 mV
• Set the FM deviation meter as :
HPF
LPF
De-emphasis : OFF
Detector
• Output power: High
• Transmitting
2 • Displayed frequency :
445.000 MHz
435.000 MHz
• Output power: High
• Transmitting
1 • Displayed frequency :
DTMF
DEVIATION 445.000 MHz
(USA-3,SEA 435.000 MHz
• Push [D] key while transmitting
only)
1 • Displayed frequency:
TONE CALL
DEVIATION 435.000 MHz
(EUR, ITA • Push [TONE] key while transmit-
ting
only)
ADJUSTMENT PROCEDURES
MEASUREMENT
UNIT
1F
[USA-3]
[Other]
Top
[USA-3] panel
[Other]
Top
panel
[USA-3]
[Other]
Top
panel
: OFF
: 20 kHz
: (P–P)/2
[USA-3]
[Other]
Top
[USA-3] panel
[SEA]
Top
panel
5 - 1
LOCATION
Connect a digital 1.3 V
multimeter or an
oscilloscope to the
"VLV".
0.9 V – 1.7 V
Connect a digital 2.2 V
multimeter or an
oscilloscope to the
"ULV".
1.9 – 2.5 V
Loosely couple a 445.0000 MHz
frequnecy counter [USA-3]
to the antenna con- 435.0000 MHz
nector. [Other]
Connect an RF 5.5 W
power meter to the
antenna connector.
0.5 W
5.5 – 6.0 W
0.5 W
Connect an FM ± 4.3 kHz
deviation meter to
the antenna con-
nector through an
attenuator.
± 4.3 kHz
Connect an FM ± 3.5 kHz
deviation meter to
the antenna con-
nector through an
attenuator.
Connect an FM ± 3.5 kHz
deviation meter to
the antenna con-
nector through an
attenuator.
ADJUSTMENT
POINT
VALUE
UNIT ADJUST
DUAL-
VCO
1F
2F
2F
LOGIC
LOGIC
L303
Verify
L301
Verify
C369
R302
R316
R304
R313
R308
R314
R147
R147