Radio Shack TRC-447 Service Manual

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IC AND TRANSISTOR VOLTAGE CHART
IC's Unit [V] Unit [V]
Symbol
No.
Pin
TX WXRX
Comment
PA
Mode
Pin
1 5.9 5.9 5.9 5.9 OSC
2NC
3 5.4 5.4 5.4 5.4 MIXER OUTPUT
4 6.0 6.0 6.0 6.0 VCC
5 4.9 4.9 4.9 4.9 LIMITER INPUT
6 4.9 4.9 4.9 4.9 DECOUPLING
7 4.9 4.9 4.9 4.9 DECOUPLING
IC102 8 6.0 6.0 6.0 6.0 QUADRATURE IN
9 2.6 2.6 2.6 2.6 AUDIO OUT
10 0.9 0.9 0.9 0.9 FILTER INPUT
11 2.7 2.7 2.7 2.7 FILTER OUTPUT
12 -0.2 -0.2 -0.2 -0.2 SQUELCH INPUT
13 NC
14 0.0 0.0 0/4.9 0.0 WX OFF/1mV
15 0.0 0.0 0.0 0.0 GND
16 1.9 1.9 1.9 1.9 RF INPUT
1 2.1 2.1 2.1 2.1 XIN
2 0.0 0.0 0.0 0.0 VSS
3 2.4 2.4 2.4 2.4 RPD
4NC
5NC
6 2.2 2.2 2.2 2.2 F-R
7 0.0 0.0 0.0 0.0 LE
IC301 8 134kHz Clock Pulse CLK
9 0-5V Data Pulse DATA
10 2.8 0.0 0.0 0.0 LD
11 2.2 2.2 2.2 2.2 F-T
12 NC
13 NC
14 3.7 2.5 4.9 4.9 TPD
15 5.0 5.0 5.0 5.0 VDD
16 2.1 2.1 2.1 2.1 XOUT
1 5.0 5.0 5.0 5.0 VOUT
IC402 2 5.0 5.0 5.0 5.0 VIN
3 0.0 0.0 0.0 0.0 VSS
1 0.0 0.0 0.0 0.0 GND
IC403 2 8.0 8.0 8.0 8.0 IN
3 5.0 5.0 5.0 5.0 OUT
1 0.0 0.0 0.0 0.0 A0
2 0.0 0.0 0.0 0.0 A1
3 0.0 0.0 0.0 0.0 A2
IC405
4 0.0 0.0 0.0 0.0 GND
5 0.5 0.5 0.5 0.5 SDA
6 0.5 0.5 0.5 0.5 SCL
7 0.0 0.0 0.0 0.0 WP
8 5.0 5.0 5.0 5.0 VCC
Symbol
No.
Pin
TX WXRX
Comment
PA
Mode
ALERT
1 3.5V@UP/2.5V@NOM/1.3V@DOWN PTT_CH
2 4.5V@CH9/2.5V@NOR/0V@CH19 CH_MODE
3 5V@MON ON / 0V@MON OFF MON
4 0-3V Alert Pulse @ Alert SAME
5 2.5 2.5 0.0 1.7 0.0 PA_WX
6 0.0 0.0 0.0 - 4.9 SC
7 5V@DUAL ON / 0V@DUAL OFF DUAL
8 5.0 0.0 5.0 5.0 5.0 SQL
9 0.0 0.0 0.0 0.0 0.0 AVss
10 5.0 0.0 - - - TX/RX
11 4.9 4.9 4.9/0 4.9 0.0 WXMUTE
12 0.0 0.0 0.0 0.0 0.0 NOT USE
13 Edge @ Rotary SW Change CHDN
14 Edge @ Rotary SW Change CHUP
15 WX ALERT PULSE @ ALERT ALOUT
16 PLL Clock Output CLK
17 5.0 5.0 5.0 5.0 5.0 Vdd1
18 PLL/EEPROM Data Output DATA
19 PLL LE Output LE
20 NC
IC401 21 0-4V Switching Pulse LED-COM
22 0.0 0.0 0.0 0.0 0.0 Vpp
23 NC
24 0.0 0.0 0.0 0.0 0.0 GND
25 5.0 5.0 5.0 5.0 5.0 /RESET
26 5.0 5.0 5.0 5.0 5.0 X2
27 0.0 0.0 0.0 0.0 0.0 X1
28 0.0 0.0 0.0 0.0 0.0 Vss0
29 5.0 5.0 5.0 5.0 5.0 Vdd0
30 EEPROM Clock Output E_CLK
31 0-5V LED Switching Pulse LED-C
32 0-5V LED Switching Pulse LED-G
33 0-5V LED Switching Pulse LED-A
34 0-5V LED Switching Pulse LED-F
35 0-5V LED Switching Pulse LED-B
36 0-5V LED Switching Pulse LED-E
37 0.0 0.0 0.0 0.0 0.0 Vss1
38 0-5V LED Switching Pulse LED_D
39 6.3V@WX LED ON/0V@OFF WXLED
40 0.0 2.0 2.0 0.0 0.0 RX_LED
41 2.8 0.0 2.8 2.8 - CBMUTE
42 0.0 0.0 8.0 8.0 - CB_MON
43 5.0 5.0 5.0 5.0 5.0 AVdd
44 5.0 5.0 5.0 5.0 5.0 AVref
1 2.5 2.5 2.5 2.5 - AGND
2 2.5 2.5 2.5 2.5 - TIP
3 2.1 2.1 2.1 2.1 - RING
IC104 4 2.1 2.1 2.1 2.1 - TRQ
5 0.0 0.0 0.0 0.0 - GND
6 2.2 2.2 2.2 2.2 - OSC IN
7 2.2 2.2 2.2 2.2 - OSC OUT

Radio Shack TRC-447 Specifications

General

Brand	Radio Shack
Model	TRC-447
Category	Radio
Language	English