Kenwood TK-780 Service Manual Supplement page 53

Receiver Section
Item Condition
1. Discriminator 1) Set test mode
CH : CH1 - Sig1 - Narrow
SSG output : –53dBm
AF : 0.45V/4
2. Sensitivity 1) Set test mode
Select "SENS" in tuning mode.
"L SENS"
SSG freq'
K, HK : 146.050MHz
K2,HK2 : 136.050MHz
SSG output : –118dBm/0.31 V AG
SSG MOD : 3kHz
AF output : 1V/4
2) "C SENS"
SSG freq'
K,HK : 160.050MHz
K2,HK2 : 149.050MHz
3) "H SENS"
SSG freq'
K,HK : 173.950MHz
K2,HK2 : 161.950MHz
3. Squelch 1) Set test mode
Select "SQL" in tuning mode.
SSG freq'
K,HK : 160.050MHz
K2,HK2 : 149.050MHz
SSG output
: Value of 12dB SINAD
SSG MOD : 3kHz (Wide)
4. Image 1) Set test mode
response CH : CH2 - Sig1
Wide or Narrow
(HK only) SSG output : –30dBm
SSG freq' : 235.750MHz
SSG MOD : OFF
SQ : OFF
5. Squelch 1) Set test mode
check CH : CH1 - Sig1
SSG output : 15dB SINAD level
2) SSG output : OFF
6. QT check 1) Set test mode
CH : CH1 - Sig5
SSG MOD
INT : 1kHz
EXT : 151.4Hz
SSG system MOD DEV
: 3.75kHz
SSG output : 10dB SINAD level
2) CH : CH1 - Sig4
CH1 - Sig6
CH1 - Sig7
ADJUSTMENT
Measurement
Test-
Unit
equipment
SSG Rear
panel
AF VTVM
Oscilloscope
SSG
AF VTVM
Distortion
meter
Oscilloscope
1.5kHz (Narrow)
Adjustment
Terminal Unit Parts
ANT TX-RX L6 AF output maximum. Maximum point +0mV, –20mV.
(A/2)
ACC
(EXT.SP)
ANT Adjust for
maximum SINAD.
ACC
(EXT.SP)
Adjust for
maximum SINAD.
Adjust for
maximum SINAD.
Squelch closed
once.
Then squelch must
be opened.
TX-RX TC1 Adjust for maximum
(A/2) noise level
Check
Check
TK-780/H
Specifications/Remarks
Method
Squelch must be opened.
(Wide/Narrow)
Squelch must be closed.
(Wide/Narrow)
Squelch must be closed.
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