Kenwood TH-D74E Service Manual page 21

Pin No. Name I/O
29 I2CCKR O I2C CLK signal for radio IC
30 GND - GND
31 I2CDTR I/O I2C DATA signal for radio IC
32 GND - GND
33 SCPU_TXD I UART for SUB MPU
34 BFMS O Band B switch signal for power
35 SCPU_RXD O UART for SUB MPU
36 VINOK O VINOK signal
37 /S_RST I RESET signal for SUB MPU
38 BAT_DET O Battery S terminal detect signal
39 40CS I 40C switch signal
40 VDCIN O Detection signal for DC IN voltage
41 33SS I 33S switch signal
42 POSWO I Power switch output signal
43 Freq O NC
44 AGCA/APC I Band A AGC signal & APC signal
45 VCOMOD I Modulation signal for VCO
46 VBAT O Battery voltage detect signal
47 BPFB I Band B BPF adjustment signal
48 NC - No connection
49 33RAD O 33RAD power supply
50 +B1 O +B power supply
2.3.3 TX-RX UNIT (XC1-138)(3/7) VCO-A
Pin No. Name I/O
CN500(to TX-RX)
1 VCO_A O Band A VCO signal
2 Fin_A I Band A PLL RF input signal
3 GND - GND
4 GND - GND
5 GND - GND
6 GND - GND
7 GND - GND
8 NC - NC
9 33CA I 33CA power supply
10 GND - GND
11 GND - GND
12 GND - GND
13 GND - GND
14 GND - GND
15 SHIFT_A I Band A VCO shift signal
16 CV_A I Band A lock voltage
Function
supply(76-108MHz)
Function
2.3.4 TX-RX UNIT (XC1-138)(4/7) VCO-B
Pin No. Name I/O
CN400(to TX-RX)
1 VCO2 I Band B switch signal for
2 CV_B I Band B lock voltage
3 33BF I Band B VCO Power supply
4 GND - GND
5 UCW_VCO - NC
6 GND - GND
7 VCO1 I Band B switch signal for
8 GND - GND
9 SHIFT_B I Band B VCO shift signal
10 VCO_MOD I Modulation signal for VCO
11 GND - GND
12 GND - GND
13 GND - GND
14 NC - NC
15 GND - GND
16 VCO_B O Band B VCO signal
2.3.5 TX-RX UNIT (XC1-138)(5/7) MW/SW
Pin No. Name I/O
CN181(to TX-RX)
1 FMOUT O FM Radio RF signal
2 BFMS I Band B switch signal for
power supply(76-108MHz)
3 GND - GND
4 SWANT_S I SW bar antenna on/off switch signal
5 HFIN I Band B HF RF signal
6 GND - GND
7 GND - GND
8 MWANT_S I MW bar antenna on/off switch signal
9 BHFS I Band B switch signal for
power supply(0.1-76MHz)
10 GND - GND
11 GND - GND
12 OBPFB I Band B BPF adjustment signal
13 HFOUT O Band B HF RF signal
14 GND - GND
15 GND - GND
16 OAGCB I Band B AGC signal
17 GND - GND
18 GND - GND
19 47C I 47C power supply
20 47C I 47C power supply
Function
power supply(VCO2)
power supply(VCO1)
Function
(No.RA044<Rev.001>)1-21