Kenwood TS-2000 Service Manual page 26

TS-2000/X
DISPLAY UNIT (X54-3320-00)
Ref. No. Use / Function
Q1~3 AVR
IC1 LCD driver
IC2 LCD driver
IC3 LCD driver
IC4 Serial/parallel
D1 LED
D2 LED
D3~9 LED
TX-RX 1 UNIT (X57-605X-XX)
Ref. No. Use / Function
Q1 RF mute
Q2 Switching
Q3 Switching
Q4 Switching
Q5 Switching
Q6 Switching
Q7~10 RX 1st mixer
Q11 Switching
Q12 RF amplifier
Q13 Amplifier
Q14,15 Switching
Q16,17 Switching
Q18 Amplifier
Q19,20 RX 2nd mixer
Q21 Switching
Q22 Amplifier
Q25 Amplifier
Q26 Amplifier
Q27 DC amplifier
Q28 Amplifier
Q29 Switching
Q30 Buffer amplifier
Q31 Switching
Q32 Amplifier
Q33 Switching
Q34 Switching
Q37 Switching
Q38 Amplifier
Q40 Switching
Q41 Amplifier
Q42 Buffer amplifier
26
DESCRIPTION OF COMPONENTS
Operation / Condition
LCD backlight
LCD 7-segment driver (B-SEG)
LCD 7-segment driver (A-SEG)
LCD dot segment driver
LED control, backlight dimmer control
On when VOX is selected
On when PROC is selected
Key illumination
Operation / Condition
On in HF/50MHz TX mode
On in HF/50MHz RX mode
Q2 control
Dedicated external RX antenna
changeover relay control
HF/50MHz RF ATT control
On in 50MHz TX mode
RX 1st IF 69.085/75.925MHz
Off when HF/50MHz preamplifier on
When HF-21.5MHz
1st local oscillation amplifier
Q12 control
Q16 turns on when first IF change-
over control is 75.925MHz
RX 1st IF 69.085/75.925MHz
Converts RX 1st IF to 10.695MHz
Reserved
For NB 10.695MHz
RX 2nd IF amplifier 10.695MHz
NB amplifier 10.695MHz
NB AGC amplifier
NB amplifier 10.695MHz
On at time of NB blanking
Impedance changeover
On at time of NB blanking
RX 3rd local oscillation amplifier
(11.150MHz)
On when 1st IF frequency is 69.085MHz
Creates RXB in FM mode
Creates RXB in non-FM mode
3rd IF amplifier (455kHz)
On during RX in non-FM mode
RX 4th local oscillation amplifier (467kHz)
4th IF frequency (12kHz)
Ref. No. Use / Function
Q43 Amplifier
Q44,45 TX 3rd mixer
Q46,47 TX 2nd mixer
Q48 Buffer amplifier
Q49 TX 2nd IF amplifier
Q51 Switching
Q52 DC buffer amplifier
Q53 Switching
Q54 TX 2nd IF amplifier
Q57 Switching
Q58 Limiter
Q59 Oscillator
Q60 Switching
Q61,62 Mute
Q63,64 DC-DC oscillator
Q65 Switching
Q66 Switching
Q67 Switching
Q69,70 AVR
Q71,72 Switching
Q73,74 Amplifier
Q75 Switching
Q76 Amplifier
Q77 Switching
Q78,79 Amplifier
Q80~91 Switching
Q92 Switching
Q93 Buffer amplifier
Operation / Condition
HF/50MHz TX drive amplifier
Converts 68.985/75.825MHz to TX
frequency
Converts 10.695MHz to 68.985/
75.825MHz
10.695MHz
10.695MHz
Keying control
ALC keying control
On during TX in non-FM mode
10.695MHz
On during transmission in FM mode
FM modulation signal limiter
(elimination of AM component)
FM oscillator, modulation 10.595MHz
On during TX in non-FM mode
On when main and sub are
simultaneously AF muted
–6V generation
On when relay for HF band linear is used
On when relay for HF band linear
is transmission
On when relay for HF band linear is used
AVR for mobile controller
(Power about 9.4V)
50MHz/VHF/UHF/1.2GHz band
external linear control
ALC amplifier
On in AM mode, makes it an
average value type ALC
ALC amplifier
Turns on and lowers the power at
time of protection
ALC amplifier
Produces the respective TXB and
RXB from 8C to HF/50MHz, VHF
band, UHF band and 1.2GHz bands.
The synthesis of the TXB becomes
IF TXB and the synthesis of the
RXB becomes IF RXB.
This control voltage is necessary
for simultaneous TX/RX, such as
for satellite communication.
Cancels the time constant for VSF
and VSR voltage lines during
antenna tuning
Buffer amplifier for external
modulation input signal