Kenwood 144MHz FM TRANSCEIVER K2E - Manual (Page 16)

TH-K2AT/K2E/K2ET
16
D33
Reverse current
Battery
prevention
D34
AVR
constant-voltage
D35
Reverse current
Battery
prevention
D36
Reverse current
DC IN
prevention
D40 TX LED Lights on TX
D41 BUSY LED Lights on RX
D42-44 Key illumination
Key backlight illumination
D46,47 LED
D48,49
LCD illumination
LCD backlight illumination
LED
D60
Key type
detection
D62-65
market code
detection
D69-72
Reverse current
Key matrix
prevention
D73 Voltage drop
D74,79 Limiter
D80
Reverse current
prevention
COMPONENTS DESCRIPTION
Q34
Q33 operation
On when charging
switch
Q35 DC IN detection H: DC IN detection
Q36
Ni-MH temperature On when temperature detection is
detection activated
Q37
AF amplifier/
Lamp AVR
Q38
Q37 operation On when the speaker outputs audio or
switch lamp lights
Q41 5MS switch On when 5MS is applied
Q47
TX/BUSY LED
switch
Q50 Key LED switch On when the key LED lights
Q51 LCD LED switch On when the LCD LED lights
Q52 Beat shift switch
Q53 5R/5MV switch On when 5R or 5MV is applied
Q55 5T switch On when 5T is applied
Q56
Speaker mute
switch
Q57 5C switch On when 5C is applied
Q58
Q12 gate
Off when High power is selected
voltage switch
Q59
WX detection
amplifier
D1,2
VCO frequency
control
D5 Frequency shift
D6 VCO modulation
D7 Speed up Ripple filter
D8 RF switch On TX
D9 RF switch On RX
D10-13 Antenna switch On TX
D14
Reverse current
APC reference voltage
prevention
D15
APC output
voltage limiter
D16 PLL lock detection
D17
Over input
protection
D18-21 RX BPF tuning
D22 MIC mute control
D24
VOX detection
rectification
D25
Speaker mute
speed up
D26 C246 discharge
D27
MIC ALC
rectification
D30
Reverse current
Charge current
prevention
D31
Constant-current
Constant-current charge
circuit
D32
Reverse current
DC IN
prevention
Ref. No. Use/Function Operation/Condition/Compatibility Ref. No. Use/Function Operation/Condition/Compatibility