Kirisun PT558, Service Manual

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potentiometer VR1, and watch the demodulation signals. The wave
shape should be smooth (close to square wave) and then adjust the
figure to set the frequency deviation at 0.35kHz.
6.3.7 CTCSS Frequency Deviation Adjustment
Under the computer test mode, select CTCSS wide band
modulation , and click adjustment to enter. Adjust the figure to
set the frequency deviation at 0.35kHz.
6.3.8 Receiver Sensitivity
Repeat adjusting L9, L10, L6, and L5 to make the frequencies
at highest sensitivity.
6.3.9 Receiver Squelch Setting
Under the computer test mode, select the 9th squelch and
click adjustment to enter. Input the receiver with the signals of
1kHz modulation frequency, 3kHz frequency deviation, and -
117dBm level. Adjust the figure to make the green light flash.
Under the computer test mode, select the 1st squelch and
click adjustment to enter. Input the receiver with the signals of
1kHz modulation frequency, 3kHz frequency deviation, and 124dBm
level. Adjust the figure to make the green light flash.
6.4 Debugging
The above debugging refers to Table3, Table4, and Table 5.
Table 6.3 Voltage Controlled Oscillator (VCO)
Table 6.4 Receiver
Band
Pass
Filter
Spectroan-
alizer/
Item Test
Condition
Test
Equipment
Test
Point
Adjustment
Part
Require
-ment Note
Setting Battery
Power:
7.5V Multimeter
PD
Locked CH:RX Low
Frequency
C180 1.0V 0.1V
Watch
Adjust
-ment
Digital
Power
Item Test
Condition
Test
Equipment
Test
Point
Adjustment
Part
Require
-ment Note
Compreh
-ensive
Test
Device
Before
Mixing L9 L10
L7 L6
L5
ModePass
Band
25MHz,
smooth
wave
Shape
Not
recom-
mend
the user
to adjust
it!
Audio
Level
Ch: RX
center
frequency
RF OUT
-53dBm
(501
V)
MOD:1kHz
DEV:
1.5
(kHz)
Audio
Load:16
RF Audio
Signal
Generator
Oscillator
Speak
er
Conne
ctor
(Turn the
volume
knob
clockwise)
Audio
power
0.3 W Inner
speake
r power
1.2W
High
Frequency
CH:TX
Lower
than 3.5V
Item Test
Condition
Test
Equipment
Test
Point
Adjustment
Part
Require
-ment Note
CH: MF Sensit
ivity
CH: LF
CH: HF
RF OUT:
-116dBm
(0.35
V)
MOD:1kHz
DEV:
1.5kHz
(W/N)
RF Audio
Signal
Generator
Oscillator
Audio
Voltmeter
Distortion
Test
Device
/Comprehe
nsive Test
Device
Speak
er
Conne
ctor
SINAD
12dB or
higher
Ch: RX
Center
Frequency Squel
ch
Activa
tion
Sensit
ivity
Computer
Test Mode
After
adjustmen
t, squelch
activation
is normal.
Computer
Test Mode
9th
RF OUT:
-117dBm
After
adjustment,
squelch
activation
is normal.
3rd
RF OUT:
-124dBm
Item Test
Condition
Test
Equipment
Test
Point
Adjustment
Part
Require
-ment Note
Table 6.5 Transmitter
TX
Frequ
ency Frequency
Meter/
Comprehe
nsive Test
Device Anten Computer
Test Mode Within
200Hz
±
Power Power
Meter/
Comprehe
nsive Test
Device/
Ammeter Computer
Test Mode Adjust to
4W Within
200H
z
±
Maxim
um
Modul
ation
Frequ
ency
Deviati
on
CH: TX
Center
Frequency
AG:1kHz/
70mV
Frequency
Deviation
Meter/
Comprehe
nsive Test
Device
Adjust to
±2 .2kHz
±
200
Hz
Modul
ation
Sensiti
vity AG:1kHz/
7mV
Checking
frequency
deviation:
1.1kHz~
2.0kHz
Wave
shape is
close to
smooth
square
wave.
DCS
Wave
Shape
(Balan
ce)
Oscillator /
Comprehe
nsive Test
Device
VR1
PT558 SERVICE MANUAL
VR2
L9 L10
L7 L6
L5