13
PT4200
SERVICE MANUAL
Chapter 7 Major Specifications
7.1 General Specification
Model
PT4200
Frequency (1)420~470MHz (2)400~450MHz
Modulation 11K F3E
Number of Channels
16(15+S)
Channel Spacing
12.5 kHz
MF
1st MF
49.95 MHz 2nd MF
450kHz
Working Voltage 7.5V
Working Temperature
-25
~ +55
Antenna Impetance
50
Mic Impedance
2k
Battery (Standard)
Model
KB-58A
Li-Ion Battery DC 7.2V ,
1000mAh
Dimension (WXHXD)
56 mmx120 mmx29 mm
Weight
235
With battery and Antenna
7.2 Receiver
Item
Test
Condition
Test
Equipment
Test
Point
Adjustment
Part
Require
-ment
Note
CTCSS
DEV
CTCSS:
67Hz
Battery
Power
Warnin
g
Adjust
to 0.75kHz
±
After
adjustment,
the indicator
flashes.
±
50Hz
Battery
Terminal:
6.8V
Computer
Test Mode
DCS
DEV
DCS
023N
Frequenc
y
Deviation
Meter/
Compreh
ensive
Test
Device
Adjust
to 0.35kHz
±
±
50Hz
Anten
na
Chapter 8 Trouble Shooting
No
display
after
switching
on the
radio.
A. Battery power may be insufficient. Recharge or
change the battery pack.
B. The power switch is broken, and please change it.
C. The CPU is broken, and please change it.
D.The regulator IC12 is broken, and please change
it.
PLL is
unlocked.
(Beep
sounds)
A. The PLL crystal oscillator C4 is broken, and please
change it.
B. The oscillatingtube is broken, and please change it.
C. The oscillatingtube is broken, and please change it.
Cannot
talk to or
hear
other
group
members.
A. Make sure the two communication radios are
using the channel of the same frequency.
B. Make sure the CTCSS/DCS tone is the same as
that of your group members.
C. Out of the effective communication range.
Cannot
receive
signals.
A. The antenna is not well connected, and please
screw the antenna again until secure.
B. The sensitivity is too low and minitrim L9, L10, L7,
L6, and L5.
C.HF amplifier Q20 is broken, and please change it.
D. The squelch level is too high and the squelch
cannot be activated. Reset the squelch level with a
computer.
E. Mixer tube Q19 is broken, and please change it.
F. MF processing chip IC5 is broken, and please
change it.
1
2
3
4
PROBLEM
SOLUTION
No
.
Available Sensitivity
(12dBSINAD)
Squelch Activation
Sensitivity
Receiver Surplus
Output
Modulation Receiving
Bandwidth
Adjacent Channel
Selectivity
Intermediation
Reject Ratio
Spurious Response
Reject Ratio
Audio Output
Power
Receiving Current
Sinking
Standby Current
(Average)
0.35
V
0.20
V @level 3 squelch
-40dB
3.5kHz
60dB
60dB
70dB
500mW
@distortion
5%
4
250mA
25mA
RF Power
Frequency Stability
Maximum Modulation
Frequency Deviation
Modulation Sensitivity
Modulation
300~3000Hz
Adjacent Channel
RF Power
Spurious and
Harmonics
Residential Frequency
Modulation
Transmitting Current
Sinking
4.0W @7.5V DC
-6
2.5x10
2.5kHz
16mV
3%
-60dB
-70 dB
-40 dB
1.8A @ 7.5V DC
Содержание PT4200
Страница 1: ...PT4200 PROFESSIONAL TWO WAY RADIO V060802 SERVICE MANUAL FM PORTABLE RADIO ...
Страница 24: ...22 PT4200 SERVICE MANUAL Figure 1 PT4200 Top Board Position Mark Diagram ...
Страница 25: ...23 PT4200 SERVICE MANUAL Figure 2 PT4200 Bottom Board Position Mark Diagram ...
Страница 26: ...24 Figur3 PT4200 Schematic Circuit Pane Diagram ...
Страница 27: ...8 25 Figur4 PT4200 Schematic Circuit Pane Diagram ...
Страница 28: ...KBC 58L Schematic Circuit Diagram Figure 5 KBC 58L Schematic Circuit Diagram 8 26 ...