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HKLN4216A
November 24, 2003
UHF Troubleshooting Tables:
Troubleshooting Table for Board and IC Signals
10-7
U110
RF Power Amp
1
RF input
0
(TX mode)
2
Vgg (gate bias)
2.65 (typ)
(TX mode) (4.25V typ at VHF)
3
Vdd
6.59
(TX mode)
4
RF output
--
Do not measure
5
Ground
GND
U150
Dual Opamp
1
Unit 1 output
4.20 (typ)
(TX mode) (5.8V typ at VHF)
2
Unit 1 (-) input
2.39 (typ)
(TX mode)
3
Unit 1 (+) input
2.39 (typ)
(TX mode)
4
Ground
GND
5
Unit 2 (+) input
3.30 (typ)
(TX mode)
6
Unit 2 (-) input
3.35 (typ)
(TX mode)
7
Unit 2 output
2.23 (typ)
(TX mode)
8
Vcc
6.79
(TX mode)
U201
Freq Synthesizer
1
AUX2 output (NU)
0
2
AUX3 output (TRB)
0.03
To U251-19 (RX mode)
3
AUX4 output (NU)
0
4
Lock detect output
2.98
To U401-56
5
PD Vdd
2.98
6
Digital ground
GND
7
Serial data input
3.23
8
Serial clock input
0
9
Synth chip select
3.23
From U401-47
10
Modulation input
1.50
From U451-40
11
VMULT4 (NU)
2.98
12
VMULT3 (NU)
0
13
VRO
4.96
14
VMULT2
1.49
15
VMULT1
1.49
16
INDMULT (NU)
0
17
NC1
0
18
Ref select (NU)
0
19
Buffered 16.8 MHz out
1.54
20
Analog Vdd
3.00
21
V bypass (NU)
1.55
22
Analog ground
GND
23
Ref osc XTAL1
2.07
Table 10-4. Troubleshooting Table for Board and IC Signals (Continued)
IC Designator
Pin
Pin Function
DC Voltage
Comments (Condition)
Содержание EP450
Страница 31: ...November 24 2003 HKLN4216A 4 8 VHF Theory Of Operation Keypad Notes ...
Страница 77: ...November 24 2003 HKLN4216A Notes 7 8 403 440 MHz UHF Theory Of Operation Keypad ...
Страница 85: ...November 24 2003 HKLN4216A Notes 8 8 438 470 MHz UHF Theory Of Operation Keypad ...
Страница 93: ...November 24 2003 HKLN4216A Notes 9 8 465 495 MHz UHF Theory Of Operation Keypad ...
Страница 109: ...November 24 2003 HKLN4216A Notes 10 16 UHF Troubleshooting Tables Troubleshooting Table for Board and IC Signals ...
Страница 113: ...November 24 2003 HKLN4216A Notes 11 4 UHF Schematic Diagrams Overlays and Parts Lists Speaker and Microphone Schematic ...