Pll And Car Section; Receiver Section - Kenwood TK-80 Service Manual

PLL and CAR Section

Item Condition
1. Reference 1) M CH: 01
frequency
adjustment
2. 62.35MHz 1) M CH: 01
adjustment
3. 10.695MHz 1) M CH: 01
adjustment
4. 54MHz BPF 1) M CH: 01
adjustment
5. VCO1 1) M CH: 02
lock voltage
check 2) M CH: 03
6. VCO2 1) M CH: 04
lock voltage
check 2) M CH: 05
7. VCO3 1) M CH: 06
lock voltage
check 2) M CH: 07
8. LO1 1) M CH: 08
level check Pull out CN501 (LO1).
Insert CN501 after the check. terminated
9. LO2 1) M CH: 08
(62.35MHz) Pull out CN502 (LO2).
level check Insert CN502 after the check.

Receiver Section

Item Condition
1. AGC 1) M CH: 08
adjustment
2. MCF 1) Pull out CN502 (LO2).
adjustment M CH: 08
Spectrum analyzer setting
TG level: –30dBm
Center f.: 73.045MHz
Frequency span: 70kHz
ATT: 10dB
V. REF: 2dB/DIV
Insert CN502 after the check.
ADJUSTMENT
Measurement
Test-
Unit Terminal Unit
equipment
f. counter TX-RX TP501 TX-RX TC501 20.00000MHz
(probe
10 : 1)
TP506
Oscilloscope TP503
TP505
D.V.M TP504 TX-RX TC503 2.0V
TX-RX TC504 2.0V
TX-RX TC505 2.0V
RF V.M CN501
50Ω
CN502 TX-RX (L531) Level check
Measurement
Test-
Unit Terminal Unit
equipment
D.V.M TX-RX TP2 TX-RX VR6
Spectrum CN7
analyzer
Tracking CN4
generator
Adjustment
Parts Method
± 20Hz
TC502 62.35000MHz ± 20Hz
L539 1.4Vp-p ± 0.2Vp-p
L513 Repeat adjustment 1.0Vp-p or more
L514 2 to 3 times as the
L515 level of 26.5MHz.
Level maximum
± 0.1V
Check 7.0V or less
± 0.1V
Check 7.0V or less
± 0.1V
Check 7.0V or less
Level check –0.5~+5.0dBm
0~+3.0dBm
0dBm or less:
Maximum for L531
Adjustment
Parts Method
2.9V ± 0.03V
L38 Repeat adjustment
L42 2 to 3 times to obtain
L43 a maximum gain.
Adjust the waveform
as shown to the
right.
TK-80
Specifications/Remarks
Specifications/Remarks
73.045 73.052
73.038
(MHz)
49