Common Section - Kenwood TK-790 Service Manual

Common Section

Item Condition
1. Frequency • Frequency range (MHz)
list K : 148~174 (TK-790/(B), 790H(B))
K2 : 136~156 (TK-790(B))
• Adjustment frequency (MHz)
CH TX
1 161.000 161.100 146.000 146.100
2 148.000 148.100 136.000 136.100
3 174.000 173.900 156.000 155.900
4 161.000 161.000 146.000 146.000
5 161.200 161.200 146.200 146.200
6 161.400 161.400 146.400 146.400
7 –
2. Setting • Receiver section
The indicated SSG output level are for maximum output.
Whenever there is no modulation desingnation,
standard modulation (MOD : 1kHz, DEV : 3kHz (Wide),
DEV : 1.5kHz (Narrow)) is indicated.
Connect the front panel (KCH-10) to the transceiver's body.
3. PLL lock 1) CH-SIG : 3-1 K
voltage CH-SIG : 7-1 K2
2) CH-SIG : 3-1 K
CH-SIG : 7-1 K2
PTT : ON
3) CH-SIG : 2-1
4) CH-SIG : 2-1
PTT : ON
4. Transmit 1) CH-SIG : 1-1
frequency Select FREQ_XXX
in tune mode
PTT : ON
ADJUSTMENT
Measurement
Test-
Unit
equipment
K K2
RX TX RX
– 162.000 161.900
4Ω dummy load
SSG
ANT
AF VTVM
Oscilloscope
Distortion meter
ACC
(SP)
DC VM TX-RX CV
Power meter (A/3)
Power meter Rear
f. counter
TK-790/
Adjustment
Terminal Unit Parts
• Signalling
CH No. Encode tone
1 None
2 100Hz square wave
3 QT 67.0Hz
4 QT 151.4Hz
5 QT 250.3Hz
6 DQT 023N
7 Single tone 1633Hz
8 DTMF [9]
9 MSK
• Transmitter section
AG
AF VTVM
MIC
PTT
TX-RX A (TC301) 1.5V
(A/3)
C (TC302)
Check
ANT Panel PF3 key CH-1 frequency
PF4 key
( B ) /H
Specifications/Remarks
Method
Decode tone
None
None
QT 67.0Hz
QT 151.4Hz
QT 250.3Hz
DQT 023N
2 tone 321.7/928.1Hz
DTMF [159]
None
Power meter
Coupler
ANT
Power
supply
DC IN
–
–
± 0.1V
8.0V or less
± 70Hz
( B )
Deviation
meter
Frequency
counter
Ammeter
+
– +
+
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