Kenwood TH-K2AT Service Manual page 16

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