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C148GTL DX ALIGNIMENT PROCEDURE
1. Test Equipment Required
a) Oscilloscope (0-5MHz).
b) DC Voltmeter (10 Volts Max., 100k ohm/Volt).
c) Frequency Counter.
2. Aiignment Procedure.
Aiignment of PLL Portion.
LATE
VERSION
STEP
PRESET ТО
CONNECTIONS
ADJUSTMENT
PROCEDURE
1
RX. Mode.
Band SW: Mid
CH
:19
Mode
:AM
Connect Oscilloscope to
TP-4 (lead of R124).
L17
Adjust for Max. reading.
2
Same as Step 1,
except CH: 40
Connect DC Voltmeter to
TP-2 (Lead of R126) .
L18
Adjust for 5.4 Volts re
ading
.
3
Saine as Step 1.
Connect Oscilloscope to
TP-3 (Lead of R84).
L19
Adjust for Max. reading.
4
Same as Step 1.
Same as Step 3
L21
Adjust for 16.490MHz.
5
Same as Step 1,
except Mode SW:USB
Same as Step 3
L22
Adjust for 16.4925MHz.
6
Same as Step 1,
except Mode SW:USB
Same as Step 3.
L23
Adjust for 16.4875MHz.
7
Same as Step 6,
except Band SW:Mid
Same as Step 3.
VR6
Adjust for 16.4875MHz.
8
Same as Step 1,
except Mode SW:CW
Connect Oscilloscope to
TP-6 (Lead of R60)
L37
Adjust for 10.695MHz.
9
Same as Step 8,
except Mode SW:USB
Same as Step 8
L38
Adjust for 10.6925MHz.
10
Same as Step 8,
except Mode SW:If>B
Same as Step 8
L39
Adjust for 10.6975MHz.
37
Summary of Contents for 148GTL-DX
Page 32: ...со SO AOJ VR2 BLOCK DI AGRAM ...
Page 33: ...SCHEMATIC DIAGRAM ...
Page 41: ...Parts Layout Top View Î37 2SB525C 1 4 1 5 ...
Page 42: ...PARTS LAYOUT Top View ...
Page 43: ...ADDED PARTS MAIN PCB Bottom View PC 879AB ...
Page 44: ...COPPER PATTERN SWR PCB CH SW PCB LED PCB CD ...
Page 48: ...го w INTERNAL DIAGRAM IC s MB87I9 ...
Page 49: ...INTERNAL DIAGRAM IC s го А ...
Page 50: ...INTERNAL DIAGRAM IC s S 0 4 2 P 25 ...
Page 58: ...со го BLOCK DI AGRAM ...
Page 59: ...PB OIO SCHEMATIC DIAGRAM ...
Page 60: ...WiRING DIAGRAM 3 5 3 6 P C 881 P C 8 8 0 ...
Page 66: ...COPPER PATTERN MAIN PCB ...
Page 68: ...P B O I O ADDED PARTS MAIN PCB H fs il 8 46 ...
Page 70: ...COPPER PATTERN SUB ASSY PCB s ...
Page 71: ...PARTS LAYOUT MIC JACK 49 ...
Page 74: ...INTERNAL DIAGRAM IC s MC14008B 1 4 Cou l 13 S 4 13 S 3 11 S2 10 S 1 16 15 14 13 12 11 10 9 52 ...
Page 75: ...сл С О INTERNAL DIAGRAM IC s OSC out Г 2 out FS PO PI P2 P3 PA P5 P6 P7 P8 MC145106 ...
Page 76: ...INTERNAL DIAGRAM IC s 14 0UT4 13 I N 4 12 lN 4 11 VEE 10 IN 3 9 I N 3 8 0UT3 TA75902P 54 ...