Kenwood TK-880 Service Manual page 54

TK-880/H
Receiver Section
Item Condition
1. Discriminator 1) Set test mode
CH : CH1 - Sig1 - Narrow
SSG output : –53dBm
AF : 0.45V/4Ω
2. Sensitivity 1) Set test mode
Select "SENS" in tuning mode.
"L SENS"
SSG freq'
K : 450.050MHz
K2 : 485.050MHz
K3 : 400.050MHz
SSG output : –118dBm/0.31µV
SSG MOD : 3kHz
AF output : 1V/4Ω
2) "C SENS"
SSG freq'
K : 470.050MHz
K2 : 498.550MHz
K3 : 418.050MHz
3) "H SENS"
SSG freq'
K : 489.950MHz
K2 : 511.950MHz
K3 : 429.950MHz
3. Squelch 1) Set test mode
Select "SQL" in tuning mode.
SSG freq'
K : 470.050MHz
K2 : 498.550MHz
K3 : 418.050MHz
SSG output : Value when 2dB
is subtracted from the
sensitivity value of 12dB
SINAD.
SSG MOD : 3kHz (Wide)
4. Squelch 1) Set test mode
check CH : CH1 - Sig1
SSG output : 12dB SINAD level
2) SSG output : OFF
5. 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
54
ADJUSTMENT
Measurement
Test-
Unit
equipment
SSG Rear
panel
AF VTVM
Oscilloscope
SSG
AF VTVM
Distortion
meter
Oscilloscope
AG
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.
Check
Check
Specifications/Remarks
Method
Squelch must be opened.
(Wide/Narrow)
Squelch must be closed.
(Wide/Narrow)
Squelch must be closed.