Kenwood TS-480HX User manual

© 2003-11 PRINTED IN JAPAN
B51-8667-00 (N)694
HF / 50MHz ALL MODE TRANSCEIVER
TS-480HX/480SAT
SERVICE MANUAL
DISASSEMBLY FOR REPAIR .................................. 2
CIRCUIT DESCRIPTION ........................................... 3
COMPONENTS DESCRIPTION ............................. 14
SEMICONDUCTOR DATA ..................................... 20
PARTS LIST ............................................................ 27
EXPLODED VIEW................................................... 50
PACKING ................................................................ 54
ADJUSTMENT ....................................................... 55
INTERCONNECTION DIAGRAM ........................... 76
PC BOARD / SCHEMATIC DIAGRAM
RF UNIT (X44-327X-XX) .................................... 78
FINAL UNIT (X45-365X-XX) (A/3)..................... 86
FINAL UNIT (X45-365X-XX) (B/3) ..................... 93
FINAL UNIT (X45-365X-XX) (C/3) ..................... 96
FINAL UNIT (X45-366X-XX) (A/3)..................... 98
FINAL UNIT (X45-366X-XX) (B/3) ................... 105
FINAL UNIT (X45-366X-XX) (C/3) ................... 108
DISPLAY UNIT (X54-3410-00) (A/3, B/3, C/3) ....... 110
TX-RX UNIT (X57-663X-XX) (A/2, B/2) .......... 116
SUB UNIT (X58-4900-XX)................................ 128
TERMINAL FUNCTION ........................................ 129
BLOCK DIAGRAM ................................................ 134
LEVEL DIAGRAM ................................................. 136
ACCESSORIES ..................................................... 140
SPECIFICATIONS ................................................. 141
Knob
(K29-9270-03)
Knob (Main dial)
(K21-1105-03)
Knob ring
(K29-9264-04)
Knob
(K29-9266-03)
Knob
(K29-9267-03)
Cabinet (Lower)
(A01-2190-02)
Knob
(K29-9265-03)
Knob
(K29-9267-03)
Panel assy
(A62-1076-03)
Key top
(K29-9263-02)
Stand
(J09-0409-03)
Microphone
(T91-0638-05)
Cabinet (Upper)
(A01-2189-02)
Panel
(A62-1079-01)
Foot
(J02-0441-05) x 4
CONTENTS

TS-480HX/480SAT
2
How to remove the torque changeover le-
ver (G02-0898-04)
1. Turn the lever section of the torque changeover lever to
the right. ( q)
2. Insert the tip of a flat-head screwdriver into the recessed
part of the torque changeover lever. ( w)
3. Lift the torque changeover lever using the tip of the flat-
head screwdriver. ( e)
Caution: Be careful not to damage the torque changeover
lever when lifting it.
4. Turn the lever section of the torque changeover lever to
the right, as in the position described in step 3. ( r)
5. Lift the torque changeover lever and remove it from the
panel ASSY.
DISASSEMBLY FOR REPAIR
q
w
e
r
How to mount the torque changeover le-
ver (G02-0898-04)
1. Insert the torque changeover lever into the mounting loca-
tion so that the three tabs align with the torque
changeover slots. (Fig.1)
2. Turn the lever section of the torque changeover lever to
the left while pressing the surface of the lever as shown in
the Fig. 2, and mount it onto the panel ASSY.
Apply the dry-surf 2400
onto the front and rear
surfaces of the torque
changeover lever.
Fig. 1 Fig. 2
Cautions for mounting the main dial knob
(K21-1105-03)
Confirm that the lever section of the torque changeover
lever is in the fully turned left position (Torque OFF) before
mounting the main dial knob.
Cautions for replacing the torque change-
over lever
Apply the dry-surf 2400 onto the front and rear surfaces
after replacing the torque changeover lever. (Do not apply the
dry surf to the lever section.)

TS-480HX/480SAT
3
Frequency Configuration
Figure. 1 shows the frequency configuration of this trans-
ceiver. All modes operate in a double conversion while trans-
mitting. FM mode operates in a triple conversion and other
modes operate in a double conversion while receiving.
CIRCUIT DESCRIPTION
PLL
LMX2360
VCO1 VCO2 VCO3
73.125~
133.095MHz
CF1
PLL REF
8.33~
8.47MHz
DDS
AD9835
DDS
AD9835
DDS REF DDS REF
73.095MHz
1st IF
10.695MHz
2nd IF
3rd IF
LO1
RX MIX
TX MIX
TX/RX
MIX
LO2
62.4MHz
x2
x2
Except
FM
RX MIX
TX
MIX
455kHz
FM IC
FM
CODEC
31.2MHz
fstd
X1
15.6MHz
10.695MHz (Except FM)
10.24MHz (FM)
CAR
CAR
DSP
AF OUT
MIC IN
FM MOD
ANT
Fig. 1 Frequency configuration
Reference Signal Generator
The reference frequency (fstd), which is used to control
the PLL frequency, oscillates at 15.6MHz in a crystal oscilla-
tion circuit (X1, Q1). This 15.6MHz signal passes through a
buffer amplifier (Q4) and is doubled in a multiplier (Q5) to gen-
erate a 31.2 MHz signal. The 31.2MHz signal is used as the
reference signal for the DDS (IC1) for the PLL reference sig-
nal of the first local oscillator (LO1) and the DDS (IC2) for a
carrier (CAR).
The SO-3 (TCXO unit) is configured as an option in this
transceiver, so that you can replace the crystal oscillation cir-
cuit (X1, Q1) with the SO-3. However, you must cut the R103
(0Ω) and R104 (0Ω) jumper wires to stop the operation of the
crystal oscillation circuit (X1, Q1) when using the SO-3.
LO1/LO2/CAR
■LO1 (the 1st local oscillator)
A frequency between 8.33MHz and 8.47MHz is output
using the 31.2MHz signal as the reference signal in the DDS
(IC1). The output signal passes through a ceramic filter (CF1)
and enters into a PLL (IC3). This signal is divided into 1/8 (1/
R) in the PLL and becomes the comparison frequency fø for
the frequency between 1.041MHz and 1.058MHz.
The VCOs (Q451, Q452, Q456) of LO1 oscillate between
73.125MHz and 133.095MHz. The oscillation output of
these VCOs enter pin 6 of the PLL (IC3), then divides into 1/N
in the PLL. The comparison frequency fø is compared with
the frequency divided into 1/N by a phase comparator in the
PLL, then locks the frequency to use it as the output fre-
quency of LO1.
In the DDS (IC1), the output frequency (8.33MHz to
8.47MHz) is swept with fDDS STEP [Hz]=10 x R/N when the
step is 10Hz or fDDS STEP [Hz]=1 x R/N when the step is 1Hz.
Therefore, LO1 covers the frequency range of 73.125MHz to
133.095MHz with 10Hz or 1Hz steps.
The PLL output generated by the above-mentioned
method is amplified at Q15 and passes through a band-pass
filter with a cutoff switching circuit, an attenuator, and a low-
pass filter, and is then sent to the RF unit (X44-327) as LO1.
■LO2 (the 2nd local oscillator)
The 15.6MHz (reference frequency) signal passes through
a buffer amplifier (Q4) and is doubled in a multiplier (Q5) to
generate a 31.2MHz signal. The resistance of the 31.2MHz
signal is distributed since it is used as the reference signal for
each DDS (IC1, IC2). The 31.2MHz signal is doubled in a
multipler (Q8, Q12) to generate a 62.4MHz signal.
The band-pass filter cuts the high harmonic of the
62.4MHz signal and the signal is sent to the RF unit (X44-327)
as LO2.

TS-480HX/480SAT
4
■CAR (carrier)
The 10.695MHz used in the local oscillation and detection
is generated by the DDS (IC2). The output signal sent from
this DDS passes through a buffer amplifier (Q10) and a low-
pass filter, and is then sent to each signal.
X1,Q1
15.6MHz
TCXO
SO-3
Q4
Buffer
Q3 Q6
Buffer
Q10
Buffer
Q5
x2
Q8 Q12
x2
IC2
DDS
Q2 Q7
Buffer
Q9 Q11
Buffer
IC1
DDS
IC3
PLL
Q451
VCO1
Q452
VCO2
Q456
VCO3
31.2MHz
D1 CF1
BPF
BPF
LPF
FM MOD
Q14
LPF LPF BPF LPF
Q455 Q15 LO1
73.125~
133.095MHz
LO2
62.4MHz
CAR
10.695MHz
8.33~8.47MHz
Fig. 2 Reference signal generator, LO1/LO2/CAR
DDS AD9835BRU (IC1)
HF TX/RX USB LSB CW CW-R CWN
Lo1 RX TX RX TX RX TX RX TX RX TX
Filter offset 1 +1.5k +1.5k -1.5k -1.5k +(1.5k-PITCH) +(1.5k-PITCH) -(1.5k-PITCH) -(1.5k-PITCH) 0 0
Filter offset 2 +0.71k +0.71k -0.71k -0.71k ------
RIT (∆ RIT) - (∆ RIT) - (∆ RIT) - (∆ RIT) - (∆ RIT) -
XIT - (∆ XIT) - (∆ XIT) - (∆ XIT) - (∆ XIT) - (∆ XIT)
IF Shift +(IF S) - -(IF S) - +(IF S) - -(IF S) - +(IF S) -
CAR correction +(CAR H) +(CAR H) -(CAR L) -(CAR L) +(CAR H) +(CAR H) -(CAR L) -(CAR L) - -
HF TX/RX CWN-R FSK FSK-R AM FM
Lo1 RX TX RX TX RX TX RX TX RX TX
Filter offset 1 0 0 -(SHIFT/2) -(SHIFT/2) -(SHIFT/2) -(SHIFT/2) 0 0 0 0
Filter offset 2 - - - - ------
RIT (∆ RIT) - (∆ RIT) - (∆ RIT) - (∆ RIT) - (∆ RIT) -
XIT - (∆ XIT) - (∆ XIT) - (∆ XIT) - (∆ XIT) - (∆ XIT)
IF Shift -(IF S) - -(IF S) - +(IF S) - - - - -
CAR correction -- -- ------
Filter offset 2 : DATA filter ON, The amount of IF shift when selecting Center “2210Hz”
(∆RIT) : RIT frequency variable amount (-9.99~+9.99kHz)
(∆XIT) : XIT frequency variable amount (-9.99~+9.99kHz)
(PITCH) : CW pitch frequency (400~1000Hz, Initial value 800Hz)
(SHIFT) : FSK shift width frequency (170Hz, 200Hz, 425Hz, 850Hz, Initial value:170Hz)
(MARK) : FSK mark frequency (H TONE : 2125Hz, L TONE : 1275Hz, Initial value : 2125Hz)
Table 1 LO1 frequency shift data
CIRCUIT DESCRIPTION

TS-480HX/480SAT
5
DDS AD9835BRU (IC2)
CAR USB LSB CW CW-R CWN
RX TX RX TX RX TX RX TX RX TX
Filter offset 1 +1.5k +1.5k -1.5k -1.5k +(1.5k-PITCH) +(1.5k-PITCH) -(1.5k-PITCH) -(1.5k-PITCH) 00
Filter offset 2 +0.71k +0.71k -0.71k -0.71k - - - - - -
CW piitch - - - - +(PIITCH) - -(PIITCH) - +(PIITCH) -
FSK tone - - - - - - - - - -
IF Shift +(IF S) - -(IF S) - +(IF S) - -(IF S) - +(IF S) -
CAR correction +(CAR H) +(CAR H) -(CAR L) -(CAR L) +(CAR H) +(CAR H) -(CAR L) -(CAR L) - -
CAR CWN-R FSK FSK-R AM FM
RX TX RX TX RX TX RX TX RX TX
Filter offset 1 0 0 -(SHIFT/2) -(SHIFT/2) -(SHIFT/2) -(SHIFT/2) Stop 0 -455k 0
Filter offset 2 - - - - - - - - - -
CW pitch -(PIITCH) - - - - - - - - -
FSK tone - - -(MARK) -(MARK) +(MARK+SHIFT) -(MARK) - - - -
IF Shift -(IF S) - -(IF S) - +(IF S) - - - - -
CAR correction ---- - - - - - -
Filter offset 2 : DATA filter ON, The amount of IF shift when selecting Center “2210Hz”
(∆RIT) : RIT frequency variable amount (-9.99~+9.99kHz)
(∆XIT) : XIT frequency variable amount (-9.99~+9.99kHz)
(PITCH) : CW pitch frequency (400~1000Hz, Initial value 800Hz)
(SHIFT) : FSK shift width frequency (170Hz, 200Hz, 425Hz, 850Hz, Initial value:170Hz)
(MARK) : FSK mark frequency (H TONE : 2125Hz, L TONE : 1275Hz, Initial value : 2125Hz)
Table 2 CAR frequency shift data
Receiver Circuit
FM mode operates in a triple conversion: the first IF
(73.095MHz), the second IF (10.695MHz), and the third IF
(455kHz). All modes other than FM mode operate in a double
conversion: the first IF (73.095MHz), and the second IF
(10.695MHz).
■From antenna to a preamplifier (Q153, 154)
There are two antenna terminals: ANT 1 and ANT 2. With
these antenna terminals, it is possible to select the terminal
to be used and store the selection for each band. A pigtail
wire is used in this transceiver to maintain the freedom of the
antenna wire when it is mounted in a car.
The receive signal sent from the antenna terminal enters
the ANT section (X45-366 C/3 : 200W transceiver, X45-365 C/
3 : 100W transceiver) of the final unit. The signal passes
through a surge trap, the antenna changeover relay, the an-
tenna tuner changeover relay (only 100W transceiver), the
transmission/reception changeover relay, and an image filter,
and is then sent from CN503 to CN2 of the RF unit (X44-327)
though a co-axial cable.
The signal input into the RF unit passes through the at-
tenuator circuit, the image filter, the surge absorption limiter,
and then enters the RF BPF. Although the default of the at-
tenuator is 12dB, it can change to approximately 20dB by re-
moving the CN4 jumper.
The RF BPF divides in the range as shown in table 3. The
transmit signal also passes through the RF BPF when trans-
mitting.
The preamplifier (Q153, 154) receives the signal passed
through the RF BPF. This transceiver obtains necessary gain
and frequency characteristic by applying NFB (Negative
Feedback) to the source earthed circuit having two parallel-
connected MOS FETs. Although the preamplifier was con-
ventionally switched by switching between low-band and
high-band, this transceiver can obtain necessary characteris-
tics for each band by switching the NFB amount of the
source at Q155.
You can turn the preamplifier ON/OFF by pressing the
[ATT/PRE] key.
Band Filter range
BC 30kHz~1.705MHz
1.8MHz 1.705~2.5MHz
3.5MHz 2.5~4.1MHz
7MHz 4.1~7.5MHz
10MHz 7.5~10.5MHz
14MHz 10.5~14.5MHz
21MHz 14.5~21.5MHz
28MHz 21.5~30MHz
30~49MHz, 54~60MHz
50MHz 49~54MHz
Table 3 RF BPF
CIRCUIT DESCRIPTION

TS-480HX/480SAT
6
■From receiving 1st mixer to the second IF fre-
quency (10.695MHz)
The output signal sent from the RF BPF passes through
the image filter and is converted to the first IF frequency
(73.095MHz) at the first receiving mixer (Q156, 157, 160,
161). The receiving first mixer has a circuit having quadruple
JFETs (Q156, 157, 160, 161). This same type of circuit is
used in high-class transceivers. Therefore, this transceiver
has the same or higher dynamic characteristics as high-class
transceivers.
Two MCF (XF151) with 2-poles are used in the next stage.
This transceiver reduces proximity spurious components of
the transmit signal by passing the narrow-band MCF. It also
reduces spurious components of the receive signal.
TP1 (CN152) and TP2 (CN252) adjust MCF. The signal
passed through the MCF is amplified at the first IF amplifier
(Q253) and converted to the second IF frequency (10.695
MHz) at the second receiving mixer (D256). The receiving
second mixer is the passive type mixer using diodes and the
transmit signal passes through it when performing transmis-
sion.
The second IF signal (10.695MHz) is sent from CN254 of
the RF unit (X44-327) to CN501 of the TX-RX unit (X57-663 A/
2) through a co-axial cable.
ANT1 ANT2
AT TX
signal
RX
TX
ATT
–12dB/
–20dB
RF BPF
30kHz~
60MHz
Q153,154
PRE AMP
Through
PRE AMP OFF
Q156,157,160,161
RX 1st Mixer
MCF
XF151
73.095MHz
Q253
1st IF AMP
D256
RX 2nd Mixer
10.695MHz
RX 2nd IF
to TX-RX (A/2)
Q255
LO2 AMP
LO2
62.4MHz
AGC
Q159
LO1 AMP
LO1
73.125~133.095MHz
RF unit
Filter unit (C/3)
ANT section
Except 200W
Fig. 3 From antenna to the second IF frequency (10.695MHz)
■10.695MHz IF filter circuit (Filter section (X57-663
B/2) of the TX-RX unit)
The TX-RX unit (X57-663 A/2) comprises the receiver cir-
cuit, the PLL circuit, the transmitter circuit (from AF to the
first IF: 10.695MHz), the AF DSP, and the control circuit.
The second IF signal (10.695 MHz) input into CN501 of the
TX-RX unit (X57-663 A/2) enters CN901 of the filter section
(X57-663 B/2). This unit has the 10.695MHz IF filter and the
IF amplifier. It is possible to remove the unit to mount a op-
tional IF filter (two pieces) and TCXO (SO-3).
The second IF signal (10.695MHz) input from CN901 is
amplified at the second receiver IF amplifier (Q901). The sec-
ond receiver IF amplifier operates as a gate of the noise
blanker. Q902 and Q901 turn OFF while blanking. Q901 am-
plifies the transmit signal.
The output signal sent from Q901 passes through the
10.695MHz IF filter and is amplified at the IF amplifier (Q971),
then returns to the TX-RX unit (X57-663 A/2) from CN971.
Table 4 shows the path of the 10.695MHz IF filter mode.
You can mount two IF filters from the following optional IF
filter types:
SSB NARROW: 1.8kHz, CW: 500Hz, and CW NARROW:
270Hz.
The option filter is automatically selected by the resis-
tance, which is set in the option filter. Therefore, you do not
need to select the filter using menu or a switch.
Filter Bandwidth RX TX
Through (R943, 945) Through FM Not used
XF931 6kHz AM AM
XF932 2.4kHz SSB/CW/FSK SSB/CW/FSK
/AM NAR /FM
Option filter 1 *1 *2 Not used
Option filter 2 *1 *2 Not used
*1: The bandwidth of the mounted IF filter is applied.
*2: The mode changes corresponding to the mounted IF filter.
The CW filter is available in SSB mode with the selection is in the
menu.
Table 4 IF filter selection
CIRCUIT DESCRIPTION

TS-480HX/480SAT
7
■From the receiver second IF to detection (TX-RX
unit (X57-663 A/2))
The path of the second IF signal (10.695MHz) input into
CN555 of the TX-RX unit (X57-663 A/2) is different between
FM mode and all other modes until the detection stage.
In modes other than FM mode, the second IF signal is
amplified at Q551 and Q554. The diode located at the sec-
ond side of the loading side coil (L553) of Q551 is a PIN diode
(D551). With the current applied to the PIN diode, the receiv-
ing total gain, which is used to start the AGC operation, is
determined in modes other than FM mode. It is possible to
change the current with adjustment menu No.1 (AGC Ref.).
The transistor (Q561) connected to the source of Q554 is
used as a switch to mute the IF signals in modes other than
FM mode while transmitting.
The signal amplified at Q554 is detected at the mixer IC
(IC553) and becomes the AF signal in SSB/ CW/ FSK mode.
IC553
Mixer IC
Q554
AGC
AMP
D551
RX ATT
Q551
AGC
AMP
IC551
FM IC
RX OUT
10.695MHz
FM IF
10.695MHz
Q971
Q558
SSB/CW/FSK
FM
CAR
10.695MHz
IFGC
Q561
Mute SW
AM
AGC
Q557
Buffer
Q556
IF AMP
Q552
AGC AMP
D552
D555
D940
TX-RX unit (A/2)TX-RX unit (B/2)
Filter section
AM 6kHz
XF931
D932
D941 D934
SSB/CW/FSK 2.4kHz
XF932 D936D931
D935D933
Option
filter 2
Option
filter 1
D935D933
D932
D940 FM
through
Q901
IF AMP
Q902
SW
NB
gate
Noise
blanker
Q508
NB IN
2nd IF
10.695MHz
RF unit TX-RX unit (A/2) TX-RX unit
(B/2)
Filter section
AGC
Q971
IF AMP
RX OUT
10.695MHz
FM IF
10.695MHz
Fig. 4 10.695MHz IF filter circuit
In AM mode, the signal amplified at Q554 passes through
Q556 and is detected at D555. Some DC bias is applied to
D555 to reduce distortion of small signals. The output signal
D552 sent from Q556 is rectified at D552 and the AGC volt-
age is generated by Q552.
In FM mode, the second IF signal enters into the FM IC
(IC551). The entered signal is converted to 455kHz. The sig-
nal is then amplified at the limiter circuit in the FM IC, where
it is detected.
Although the receive bandwidth in FM mode is decided by
the ceramic filter (CF551), the bandwidth of the filter does
not change in FM Narrow mode.
Fig. 5 From the receiver second IF to detection
CIRCUIT DESCRIPTION

TS-480HX/480SAT
8
■From detection to AF output
As for the AF signal detected in each mode, a necessary
mode for the signal is selected by the analog switch (IC733).
The AF signal is amplified at IC224 and IC218 and converted
to a digital signal by the CODEC (IC217), and is then sent to
the DSP (IC220).
In the DSP, the basic signal processing such as AF gain,
the interference elimination such as slope tune, and the noise
reduction such as NR are performed for the signal. The signal
is then converted to an analog signal again at the CODEC.
The analog signal is amplified at IC214, then re-amplified
at the AF amplifier (IC734) to drive the speaker.
To utilize the convenience of the “completely separated
panel type”, the internal speaker and the headphone terminal
is mounted in the panel and the external speaker terminal is
mounted in the transceiver.
To realize the priority of the received audio output (the
headphone (top priority), the external speaker (the second
priority), and the internal speaker (the third priority)), use the
headphone and the external speaker jack having a switch to
make each MCU (X54 IC3, X57 IC204) recognize the condi-
tion of the inserted plug and switch the relay set on the out-
put of the AF amplifier (IC734) in order to select an appropri-
ate path.
FM
AM
SSB
CW
FSK
IC733
Analog SW IC224
TX-RX unit (A/2)
IC218
(A/2)
IC217
CODEC
IC734
AF AMP
IC220
DSP
IC214
(A/2)
EXT. SP
Panel
(INT. SP/Headphone)
Fig. 6 From detection to AF output
IC220
DSP
IC221
MIC AMP
IC218
(B/2) IC214
(B/2)
IC219
Analog
SW
IC217
CODEC
IC212
DAC
FM MOD
SSB/AM/FSK
Balanced MOD
MIC
TX-RX unit (A/2)
Fig. 7 From the MIC terminal to modulation output
■From the MIC terminal to modulation output
The frequency configuration of the transmitting part is
double superheterodyne: the transmitter first IF
(10.695MHz) and the transmitter second IF (73.095MHz).
The same type 16-bit DSP as the receiver circuit is used in
the audio signal processing stage.
The MIC terminal is mounted in the transceiver and a
modular jack is also employed. This is the fist time an HF
transceiver to has had a modular jack.
The AF signal input from the MIC terminal is amplified at
the microphone amplifier (IC221) and passes through the
analog switch (IC219), where it is amplified again at IC218.
The AF signal is converted to a digital signal by the CODEC
(IC217), and is then sent to the DSP (IC220).
In the DSP,. the MIC gain, the processor, and various fil-
tering are performed for the signal and it is converted to an
analog signal by the CODEC. The analog signal is amplified at
IC214 and assigned to FM mode or a mode other than FM
mode by the DAC: IC212 (used as the electrical volume), and
is then sent to each modulation circuit.
Transmitter Circuit
There are two types of transmission output: 200W (TS-
480HX) and 100W (TS-480SAT). The 100 W transceiver has
an internal antenna tuner.
With the presence of the internal antenna tuner, the final
section (A/3), the LPF section (B/3), and the ANT section (C/3)
of the final unit is different between the 200 W transceiver
and the 100W transceiver (200W transceiver: X45-366,
100W transceiver: X45-365). The same type of the TX-RX unit
(X57-663) and RF unit (X44-327) are used in both the 200W
transceiver and the 100W transceiver, even though there is a
small constant difference.
In addition, the same type of display unit (X54-341) is used
in both the 200W transceiver and the 100W transceiver.
Signal Path Before/ After the CODEC
The signal path changes corresponding to the transmis-
sion/reception since the CODEC exchanges the signal with
the optional unit (VGS-1).
■Functions relating to transmission
1) Modulation input path
The output signal sent from the analog switch (IC219) en-
ters the CODEC, and is then sent to the DSP (IC220).
•The signal sent from the microphone is output from pin 11
to pin 10 of the analog switch.
•The signal sent from the data terminal (ANI) is output from
pin 1 to pin 2 of the analog switch.
•The message output signal (DRO) sent from the optional
unit (VGS-1) is output from pin 4 to pin 3 of the analog
switch.
2) Modulation output path
The AF signal processed at the DSP (IC220) enters the
CODEC (IC217) again and is amplified at IC214. The signal
amplified at IC214 passes through the following signal paths
in FM mode and SSB/ AM/ FSK mode. (The MIC gain is de-
cided at the DSP, not DAC (IC212), in both modes.)
•FM mode
The signal enters pin 21 of the DAC, and is then sent from
pin 22 to the FM modulation circuit (FMOD).
•SSB/ AM/ FSK mode
The signal enters pin 24 of the DAC, and is then sent from
pin 23 to the balanced modulation circuit (SMOD).
CIRCUIT DESCRIPTION

TS-480HX/480SAT
9
3) Recording a message
The signal sent from the microphone is output from pin 11
to pin 10 of the analog switch (IC219), where it enters into
the CODEC (IC217). The signal sent from the CODEC enters
pin 13 of the DAC (IC212), and is then sent from pin 14 to the
optional unit (VGS-1) to be recorded.
■Constant received audio recording function
1) Recording
A part of the received audio signal is sent from the CODEC
(IC217) to pin 13 of the DAC (IC212), and is then sent from pin
14 of the DAC to the optional unit (VGS-1) to be recorded. The
recording level is automatically compensated to become con-
stant and you cannot randomly change the level.
2) Playback
The output signal (VOI) sent from the optional unit (VGS-1)
passes from pin 1 to pin 2 of the DAC. The signal passes
from pin 8 to pin 9 of the analog switch (IC219), and is then
mixed with the input signal of the AF amplifier (IC734). The
DAC (IC212) controls the volume.
■Other functions
1) Playing a message (monitor)
The output signal (VOI) sent from the optional unit (VGS-1)
passes from pin 1 to pin 2 of the DAC. The signal passes
from pin 8 to pin 9 of the analog switch (IC219), and is then
mixed with the input signal of the AF amplifier (IC734). The
DAC (IC212) controls the volume.
2) Playing a pre-recorded voice message
The above-mentioned signal path is also used for playing a
pre-recorded voice message.
IC218 (A/2)
IC217
CODEC
IC220
DSP
12
11
13
1
5
4
8
MIC
DET
MIC
PKD
ANI
DRO
DRO
10
2
3
6
9
VOO
VOS
VOAF
IC219
Anolog SW
24
16
13
2
21 22
23
15
14
1
VOO
IC212
DAC
DRM
VOI
Option
VGS-1
FMOD
SMOD
ANO
AF OUT
IC734
AF AMP
TX-RX unit (A/2)
Fig. 8 Signal path before/after the CODEC
Q625
(1/2)
Q625
(2/2)
SSB/AM/FSK
Mod. IN
DC for
AM/FSK
Differential
input
IC621
Balanced
Mod.
DSB OUT
10.695MHz
CAR
10.695MHz
TX-RX unit (A/2)
Fig. 9 SSB/AM/FSK mode modulation circuit
Modulation Circuit
The modulation signal processed at the DSP is sent to the
modulation circuit. The circuit receiving the modulation signal
is different between FM mode and SSB/ AM/ FSK mode.
1) SSB/ AM/ FSK mode
The modulation signal sent from the DAC (IC212) enters
the balanced modulator (IC621) after inverting the phase at
Q625. The 10.695MHz transmission signal sent from the bal-
anced modulator is amplified at Q621 and is then sent to the
next stage.
•AM mode
The DC voltage is applied to the pin 1 of the balanced
modulator via D624. With the DC voltage, the AM carrier
is generated since the balanced modulator becomes un-
balanced.
•FSK mode
In conventional FSK mode, the frequency of the carrier
was changed with the external keying signal. This trans-
ceiver generates the FSK signal by changing the single
tone (AF) generated at the DSP. The balanced modulator
performs the same operation as SSB mode.
•CW/FM mode
The necessary carrier wave is obtained by making the bal-
anced modulator lose balance.
CIRCUIT DESCRIPTION

TS-480HX/480SAT
10
2) FM mode
Although the circuit directly modulating the frequency of
the VCO and the crystal oscillator was conventionally used,
this transceiver uses a phase modulation circuit.
Set the variable capacity diode (D1) on the output of the
DDS (IC1) working as the source of the reference frequency
of the PLL circuit generating the first local oscillator (LO1).
Some DC fixed bias is applied to the variable capacity diode
(D1) in order to optimise the modulation sensitivity.
Although LO2 or the crystal oscillator (10.695MHz) is
modulated in the conventional transceiver, the first local os-
cillator (LO1) is modulated in this transceiver.
L7
Ref. OSC
(31.2MHz)
IN
from Q7
FM Mod.
OUT
to Q9
R31
R34
L11
L10
D1
FM Mod.
audio IN
TX-RX unit (A/2)
Fig. 10 FM mode modulation circuit
■From the modulation circuit to 10.695MHz
The transmission signal sent from the balanced modulator
(IC621) is sent from the filter section (X57-663 B/2) of the TX-
RX unit to the TXIN terminal (pin 8) of CN555. It is possible to
remove the unit to mount an optional IF filter and TCXO. You
can mount two optional IF filters. The IF transmit signal
passes through the XF931 (passband: 6kHz) in AM mode and
XF932 (passband: 2.4kHz) in modes other than AM mode.
Although various IF filters can be selected, corresponding
to the passband and mode when receiving, the IF filter is au-
tomatically selected by mode when transmitting. The trans-
mit signal passes through the 10.695MHz IF filter, is ampli-
fied at the IF amplifier (Q901), and is then sent to the IFIN
terminal (pin 10) of CN554 of the TX-RX unit (A/2).
The IF amplifier (Q901) performs the gain varying opera-
tion with the ALC voltage while transmitting. The ALC volt-
age controls gate 2 of Q901 and the AGC voltage is applied to
gate 2 while receiving. The bias voltage transferred from
D905 is provided to the source of Q901 while transmitting.
Q903 turns ON while receiving and it discharges TXB voltage.
The transmit signal sent from the IF amplifier (Q901)
passes through D903 and D901. While D903 turns ON when
transmitting, D901 makes the attenuator operate by chang-
ing the impedance with the IFGC voltage which changes the
IF transmit signal. The level variance works as the TGC func-
tion controlling the transmit gain.
The 10.695MHz transmit IF signal returned from the IFIN
terminal (pin 10) of CN901 of the TX-RX unit (B/2) to the TX-
RX unit (A/2) is sent from CN501 of the TX-RX unit (A/2) to
CN254 of the RF unit (X44-327) through a co-axial cable.
XF932
BW : 2.4kHz
SSB/CW/FM/FSK
D936
XF931
BW : 6kHz
AM
D934 D941D938
D901
TX IF IN
10.695MHz
TX IF OUT
10.695MHz
D931
D903
D905
D902
D932
Q901
Q903
TXB
RXB TX-RX unit (B/2)
Filter section
Fig. 11 From the modulation circuit to 10.695MHz
■From 10.695MHz to the drive output
The 10.695MHz transmit IF signal input into CN254 of the
RF unit (X44-327) is converted to the transmit frequency in
LO1 and LO2 and sent from CN1 to the final unit (A/3) as a
drive output.
The 10.695MHz transmit IF signal is converted to 73.095
MHz by LO2 (62.4MHz: 4 x 15.6MHz (the reference fre-
quency) ) using the transmit mixer (D256). The D256 oper-
ates as a RX mixer while receiving mode.
The converted signal passes through D254 and is ampli-
fied at the IF amplifier (Q252). D254 can change the level of
the 73.095 MHz transmit IF signal by changing the imped-
ance with the current corresponding to the PGC voltage. The
level variance compensates the gain of the transmit signal
when performing the power control.
The 73.095MHz transmit signal passes through the MCF
(XF151) and is converted to the desired transmit frequency
by LO1 in the final transmit mixer (IC251). This transceiver
can reduce proximity spurious components since the signal
passes through the MCF (passband: approximately 15kHz)
when transmitting.
The signal sent from the final transmit mixer passes
through the RF BPF and is amplified at the drive amplifier
(Q3) to drive the final stage, and is then sent from CN1 to the
final unit (A/3).
Many spurious components can be seen when the drive
output signal is analysed with the spectrum analyser. This
problem occurs when the transceiver is not properly adjusted
or the gain balance is not normal (when the input level to the
final transmit mixer (IC251) compensating the lack of gain of
the final stage is excessively high).
TX IF IN
10.695MHz
D256
TX mixer
IC251
TX mixer
Q255
Q252 XF151
LO2 IN
62.4MHz
LO1 IN
73.125~
133.095MHz
D254
MCF
73.095MHz
PGC
DRV OUT
1.8~54MHz
Q3
Drive AMP
RF BPF
1.8~54MHz
RF unit
Fig. 12 From 10.695MHz to the drive output
CIRCUIT DESCRIPTION

TS-480HX/480SAT
11
■From the drive output to antenna
The transmit signal sent from CN1 of the RF unit (X44-327)
to the final unit (A/3) is amplified to the predetermined power
in the final stage and passes through the LPF. It is then out-
put from the antenna terminal. The 100W transceiver has an
internal relay type antenna tuner operating in all bands.
1) 100W transceiver
The transmit signal input into CN1 of the final unit (X45-
365 A/3) is amplified at the pre-drive amplifier (Q1, Q2) and
the drive amplifier (Q1,Q2) in the sub unit (X58-490) and the
final amplifier (Q4, Q5).
The signal is sent from CN11 to CN102 of the final unit
LPF section (X45-365 B/3) using the co-axial cable to elimi-
nate high harmonic using the predetermined low pass filter,
and is then sent to the ANT section (X45-365 C/3) of the final
unit though a jumper wire. This ANT section has the forward
wave, reflected wave of detection circuit, the current for the
ANT2 ANT1
Pre drive AMP
Q1 Q2
DRV IN
Q1
Drive AMP
Q2
Drive AMP
Q4
Final AMP
Q5
Final AMP
TX LPF
1.8~50MHz
band
Sub unit
L502
SWR
L505L506
IC502
IC503
VSR
VSF
AT through
AT IN
K502 K502 K501
RAT
(RF unit)
IC510
IC509
Q507
Q506
D505
D504
Phase
ERROR
OUT
Amplitude
ERROR
OUT
K503
Final unit (B/3)
LPF section
Final unit (A/3)
Final unit (C/3)
ANT section
antenna tuner, the voltage detection circuit, the IN/
THROUGH changeover relay of the antenna tuner, transmis-
sion/ reception changeover relay, and the antenna
changeover relay, and obtains the transmit output from ANT1
or ANT2.
The antenna tuner has the LC tuning circuit in the final unit
(X45-365 A/3) and the detection/ control circuit in the ANT
section (X45-365 C/3) of the final unit. The operation is the
same as the conventional transceiver. The phase difference
signal of IC503 in the ANT part switches the condenser in the
input side of the final unit tuning circuit and the amplitude
difference signal of IC502 switches the condenser in the out-
put side.
The SWR is decided by calculating the voltage of the for-
ward wave and the reflected wave with the MCU (IC204).
The voltage of the forward wave and the reflected wave are
used for controlling the power, the power meter, and the
SWR protection.
Fig. 13 From the drive output to antenna (100W)
2) 200W transceiver
The 200W transceiver has almost the same circuit con-
figuration as the 100W transceiver to the drive stage.
To obtain 200W of electrical power, it has two 100W final
circuits and synthesizes electricity produced by the circuit. In
the actual circuit, the L802 splitter divides the drive output of
the sub unit (X58-490) into two final circuits. L818 synthe-
sizes the produced outputs and L820 performs the imped-
ance conversion to obtain approximately 50Ω. Although the
paths of the following steps are the same as the 100W type,
it does not have an antenna tuner.
Although the HF band of the transmit output is 200W,
100W is used for the 50MHz band by considering the heat
loss due to the downsizing.
We employed the method of synthesizing 100W outputs
to obtain 200W output. This method enables the transceiver
to operate at 13.8V supply voltage and the 200W operation of
the transceiver by using two 100W class regulated power
supplies.
This method is convenient for the fixed use of the trans-
ceiver since the existing regulated power supply can be used
by using two 100W class regulated power supplies to
achieve 200W operation. Although the voltage is applied
from two regulated power supplies to each final amplifier
(Q4, Q5, Q804, Q805), the amplifier may not work properly
when two supply voltages are significantly different and the
balance of the output synthesizing part is lost.
Therefore, this transceiver has a protection function that
monitors the voltages provided by the regulated power sup-
plies and automatically stops transmission when the poten-
tial difference between the two voltages is more than 1V.
The transceiver has another protection function monitor-
ing the heat of R816 of the final unit (X45-366 A/3) by the
thermistor (TH2) and detects the unbalance of the outputs
produced by each final amplifier, automatically reducing the
TX output power when the balance significantly degraded.
CIRCUIT DESCRIPTION

TS-480HX/480SAT
12
ANT2 ANT1
Pre drive AMP
Q1 Q2
DRV IN
Q1
Drive AMP
Q2
Drive AMP
TX LPF
1.8~50MHz
band
Sub unit
L502
SWR
VSR
VSF
K501
RAT
(RF unit)
K502
Final unit (B/3)
LPF section
Final unit (A/3)
Final unit (C/3)
ANT section
L802
L818,820
Q4
Q5
Q804
Q805
Final AMP
Fig. 14 From the drive output to antenna (200W)
3) Common functions between 100W and 200W
With the ideal design for cooling function, this transceiver
is the heavy-duty specification transceiver enabling the con-
tinuous transmission at the same full power as the fixed
transceiver while keeping its size small. However, you
should remember that in general, the heat caused by long
transmission time shortens the life of parts. Do not close the
ventilation ports located on the front and back of the trans-
ceiver.
The 200W transceiver has two fans and the 100W trans-
ceiver has one fan. The drive circuit of the fan is mounted on
the final unit (A/3) and controls the rotating speed of the fan
(OFF, slow, fast) corresponding to the generated heat.
This transceiver has a current protection circuit. The col-
lector current of each final amplifier is converted to the poten-
tial difference of the resistance (10mΩ) inserted into a power
line and the potential difference is detected at IC801 of the
TX-RX unit (A/2). The ALC protection function activates with
the IC801 output when the potential difference exceeds the
predetermined value.
With this function, the transmission output decrease and
the excessive current does not flow even if the current in the
final part is increased for any reason. In addition, the trans-
ceiver has a temperature protection circuit and a SWR protec-
tion circuit.
TX-RX unit (A/2)
Final unit (A/3)
Q8
SW
Q9
SW
*
*
14V
FAN1
FAN2*
IC204
MCU
85
86
118
13
12
IC201
Multi-
plexer
TH1
*: 200W only
Fig. 15 From the drive output to antenna
(100W and 200W common functions)
■ALC circuit and transmission power control
Although a discreet circuit has conventionally been used
for the ALC circuit, this transceiver has a new type of circuit
comprising an operational amplifier. Even though the device
is different, the ALC circuit controls the ALC voltage using
the forward wave voltage (VSF) and keeps a constant output.
The voltage detected at the forward wave voltage and the
reflected wave voltage (VSR) detection circuit of the ANT
section of the final unit (C/3) is sent to the TX-RX unit (X57-
663 A/2). The forward wave voltage is divided into a suitable
voltage at R803 and R804, corresponding to the power type
and input into pin 6 of the operation amplifier (IC802), and is
then amplified. Part of the forward wave voltage is sent to
the meter amplifier comprising the operation amplifier
(IC732).
The ALC output provided by pin 7 of IC802 passes through
the diode for reverse current prevention (D811), and is then
input into pin 10 of IC802. The output provided by pin 8 of
IC802 passes through D816, and outputs it as the ALC volt-
age. The time constant of the ALC is determined by R822,
R828, and C812 connected to the line of pin 10 of IC802.
The ALC voltage is sent to the filter section (X57-663 B/2)
of the TX-RX unit and controls the gate 2 voltage, and then
changes the transmit gain. Part of the ALC voltage is sent to
pin 13 of IC802 and amplified at the operation amplifier in
IC802, and is then output from pin 14 of IC802. The output is
input the MCU (IC204) as the ALC meter voltage (ALM) via
the multiplexer (IC201).
The transmit output control is performed by changing the
comparison voltage (POC) of the operation amplifier (IC802).
The MCU (IC204) controls the comparison voltage and out-
puts the DC voltage from pin 6 of the DAC (IC681).
CIRCUIT DESCRIPTION

TS-480HX/480SAT
13
The comparison voltage changes by changing the transmit
output on the panel. Although the transmit power control
was conventionally performed with the hardware control us-
ing the voltage of the supply line when the supply voltage
lowers, this transceiver uses the software control since the
MCU (IC204) always monitors the supply voltage. Therefore,
the transmit power gradually changes when the supply volt-
age is lower than the standard voltage (13.8V).
–
+
+
–
+
67
5
R804
R828C812
R840 D818
R803 IC802
VSF
POC
D811 9
10
8D816
IC802
8C
CKY
Q681,683
ALC
OUT
D804 D802
D807
D808
D807
EXT ALC
VSR
Current
ALC reference
Protection
R822
8C
ALC time
constant
TX-RX unit (A/2)
Fig. 16 ALC circuit and transmission power control
■Around the main microcomputer
The main microcomputer operates at 3.3V of the supply
voltage and 22.1184MHz of the clock frequency. Three de-
vices (panel microcomputer, PC serial port, and external AT)
for serial communication employing the UART function are
connected around the main microcomputer. The EEPROM
(IC202) is connected for backup purposes. The supply volt-
age monitoring circuit, including the reset circuit, is also con-
nected.
■Around the DSP
The DSP (IC220) operates at 1.8 V of the internal core volt-
age, 3.3V of the external I/O voltage, and 98.304MHz
(12.288MHz x 8) of the internal clock frequency. The firm-
ware of the DSP is transferred from the main microcomputer
with the HPI bus when the transceiver is turned ON. The HPI
bus is also used in the command communication with the
main microcomputer. The buffer IC (IC222) is connected to
the data bus to enter the logic signal.
The sampling frequency of the CODEC (IC217) is 12kHz
and the clock is provided from the DSP. There are two chan-
nels for the analog signal input into the CODEC: DET IN and
PKD/ DRO/ MIC.
One of PKD/ DRO/ MIC is selected at the analog switch
(IC219), which is mounted in the previous stage and is con-
trolled by the main microcomputer. There are two channels
for the analog signal output from the CODEC: AF OUT and
DRM/ ANO/ SMOD/ FMOD. The destination to be output is
selected from DRM/ ANO/ SMOD/ FMOD at the DAC
(IC212), which is mounted in the next stage and is controlled
by the main microcomputer.
CODEC
IC217
EEPROM
IC202
DSP
IC220
PKD/DRO/MIC
DET IN
DRM/ANO/SMOD/FMOD
AF OUT
Panel
microcomputer PC (RS-232C) External
AT
Logic signal
input buffer
IC222
Data bus
HPI bus
Main
microcomputer
IC204
Reset circuit
Reduced voltage
detection circuit
Over voltage
detection circuit
Digital Control Circuit
■Outline
The digital control circuit has a multi-chip configuration
around the main microcomputer (IC204) and it has DSP and
EEPROM, etc. (Refer to Fig. 17)
Fig. 17 Digital control circuit
CIRCUIT DESCRIPTION

TS-480HX/480SAT
14
RF Unit (X44-327X-XX)
Ref No. Use / Function Operation / Condition / Compatibility
Q1 Switching ATT changeover relay control
(OFF when ATT is ON)
Q2 Switching Receiving RATB power supply control
(ON during reception)
Q3 Amplifier Transmission drive output amplifier
Q4 Mute Mutes reception path during transmis-
sion (ON during transmission)
Q51~60 Switching BPF selection
Q151 Switching ON when preamplifier is ON.
Q152 Switching ON when preamplifier is OFF.
Q153,154 Amplifier Preamplifier
Q155 Switching Gain changeover switch for preamplifier.
ON when receiving over 21.5MHz
Q156,157 Mixer Receiving first mixer
Q158 Switching Preamplifier power supply control (ON
when preamplifier is ON.)
Q159 Amplifier RX LO1 amplifier
Q160,161 Mixer Receiving first mixer
Q251 Switching Transmission IF mute control
(Mute when ON.)
Q252 Amplifier Transmission IF amplifier
Q253 Amplifier Receiving IF amplifier
Q255 Amplifier LO2 amplifier
Q256 Switching Gain correction between bands.
ON when receiving over 21.5MHz
Q301 Switching KYS signal control (ON when KEY is
inserted.)
Q302 RX power supply
control switch
IC251 Mixer Transmission mixer
IC301 Shift register Q0: Hi when BPF of 7M band is selected.
Q1: Hi when BPF of 10M band is selected.
Q2: Hi when BPF of 14M band is selected.
Q3: Hi when BPF of 3.5M band is selected.
Q4: Hi when BPF of BC band is selected.
Q5: Hi when BPF of 21M band is selected.
Q6: Hi when BPF of 50M band is selected.
Q7: Hi when BPF of 30~60M band is selected.
Q8: Hi when BPF of 28M band is selected.
Q9: Hi when BPF of 1.8M band is selected.
Ref No. Use / Function Operation / Condition / Compatibility
Q10: Hi when ATT is ON .
Q11: Hi when preamplifier is ON.
D1 Surge absorption For ATT changeover relay
D2~5 Limter
D51 Switching ON when receiving over 1.705MHz is
selected.
D52 Switching ON when receiving under 1.705MHz
is selected.
D53 Switching ON during transmission
D54 Switching ON when receiving over 1.705MHz is
selected.
D55 Switching ON when BPF of 1.705~2.5MHz is
selected.
D56 Switching 1/2: ON when BPF of 2.5~4.1MHz is
selected.
2/2: ON when BPF of 14.5~21.5MHz
is selected.
D57 Switching 1/2: ON when BPF of 7.5~10.5MHz is
selected.
2/2: ON when BPF of 30~49MHz and
54~60MHz are selected.
D58 Switching 1/2: ON when BPF of 4.1~7.5MHz is
selected.
2/2: ON when BPF of 21.5~30MHz is
selected.
D59 Switching 1/2: ON when BPF of 10.5~14.5MHz
is selected.
2/2: ON when BPF of 49~54 MHz is
selected.
D60 Switching ON when receiving under 1.705MHz is
selected.
D61 Switching ON when BPF of 2.5~4.1MHz is selected.
D62 Switching ON when BPF of 4.1~7.5MHz is selected.
D63 Switching ON when BPF of 7.5~10.5MHz is selected.
D64 Switching ON when BPF of 10.5~14.5MHz is selected.
D65 Switching ON when BPF of 14.5~21.5MHz is selected.
D66 Switching ON when BPF of 21.5~30MHz is selected.
D67 Switching ON when BPF of 30~49MHz and
54~60MHz are selected.
D68 Switching ON when BPF of 49~54MHz is selected.
D69 Switching ON when BPF of 1.705~2.5MHz is selected.
COMPONENTS DESCRIPTION

TS-480HX/480SAT
15
Ref No. Use / Function Operation / Condition / Compatibility
D151 Switching ON when receiving preamplifier is OFF
D152 Switching 1/2: ON when receiving preamplifier is OFF
2/2: ON when receiving preamplifier is ON
D154 Switching LO1 path transmission/reception changeover
D155 Switching 73.095 MHz IF path transmission/
reception changeover
D156 Switching On when receiving preamplifier is ON
D251 Switching ON during transmission
D252 Switching IF path transmission/reception changeover
D253 Reverse current AGC
prevention
D254 Attenuator PGC
D255 Switching IF path transmission/reception changeover
D256 Mixer RX 2nd/TX mixer
D301~304 Reverse current PADDLE/KEY terminal
prevention
Final Unit (X45-365X-XX) (A/3)
Ref No. Use / Function Operation / Condition / Compatibility
Q1,2 Pre-drive amplifier
Q3 Bias control Final stage bias current control
Q4,5 Final amplifier
Q6 Switching Final power supply
Q7 Switching Q6 gate bias control
Q8,9 Switching FAN control switch
Q10 Switching Power supply control for internal AT
Q11 Switching Q10 gate bias control
Q891 Switching Relay (K891) control switch
IC1 AVR B→8C
IC2 AVR 14V→5V
IC801 Extended I/O AT coil control signal (Serial→Parallel)
IC802 Extended I/O AT output C control signal (Serial→Parallel)
IC803 Extended I/O AT input C control signal (Serial→Parallel)
IC804,805 Buffer Convert 3V to 5V.
D1,2 Temperature Final stage bias current control
compensation
D3 Surge absorption Power supply surge protection
D4 Surge absorption FAN
D801~824 Surge absorption Relay (K801~824)
D891 Surge absorption Relay (K891)
Final Unit (X45-365X-XX) (B/3)
Ref No. Use / Function Operation / Condition / Compatibility
D100 LED Backlight for KENWOOD logo
D101 Surge absorption Relay (K102)
D151 Surge absorption Relay (K152)
D201 Surge absorption Relay (K202)
D251 Surge absorption Relay (K252)
D301 Surge absorption Relay (K302)
D351 Surge absorption Relay (K352)
D401 Surge absorption Relay (K402)
D451 Surge absorption Relay (K452)
Final Unit (X45-365X-XX) (C/3)
Ref No. Use / Function Operation / Condition / Compatibility
Q501~504 Driver LPF changeover relay control
Q505 Driver ANT/AT changeover relay control
Q506,507 Signal amplifier AT phase signal amplifier
Q508 Driver Transmission/reception changeover
relay (K501) control
IC501 Extended I/O LPF control signal (Serial→Parallel)
IC502 Comparator AT control amplitude signal discrimination
IC503 D flip-flop AT control phase signal discrimination
IC509,510 Inverter
D501 High-frequency Reflected wave detection
rectification
D502 High-frequency Forward wave detection
rectification
D503 Surge absorption Relay (K501)
D504 High-frequency AT amplitude signal detection
rectification
D505 High-frequency AT phase signal detection
rectification
D506 Surge absorption Relay (K502)
D507 Surge absorption Relay (K503)
D508,509 Surge absorption Lightning surge protection
Final Unit (X45-366X-XX) (A/3)
Ref No. Use / Function Operation / Condition / Compatibility
Q1,2 Pre-drive amplifier
Q3 Bias control Final (Q4, Q5) stage bias current control
Q4,5 Final amplifier
Q6 Switching B→14V
COMPONENTS DESCRIPTION

TS-480HX/480SAT
16
Ref No. Use / Function Operation / Condition / Compatibility
Q7 Switching Q6 gate bias control
Q8,9 Switching FAN control switch
Q803 Bias control Final (Q804, Q805) stage bias current control
Q804,805 Final amplifier
Q806 Switching Final (Q804, Q805) stage bias voltage
generation
Q807 Switching Q806 gate bias control
IC1 AVR B→5V
IC2 AVR 14S→8C
IC3 AVR 14V→8V (Final (Q804, Q805) stage bias
power supply)
D2,3 Temperature Final (Q4, Q5) stage bias current control
compensation
D4 Surge absorption FAN
D5 Surge absorption Power supply surge protection
D6 Surge absorption FAN
D802,803 Temperature Final (Q804, Q805) stage bias current
compensation control
D806 Surge absorption Power supply surge protection
D807 High-frequency
rectification
Final Unit (X45-366X-XX) (B/3)
Ref No. Use / Function Operation / Condition / Compatibility
D100 LED Backlight for KENWOOD logo
D101 Surge absorption Relay (K102)
D151 Surge absorption Relay (K152)
D201 Surge absorption Relay (K202)
D251 Surge absorption Relay (K252)
D301 Surge absorption Relay (K302)
D351 Surge absorption Relay (K352)
D401 Surge absorption Relay (K402)
D451 Surge absorption Relay (K452)
Final Unit (X45-366X-XX) (C/3)
Ref No. Use / Function Operation / Condition / Compatibility
Q501~504 Driver LPF changeover relay control
Q505 Driver ANT changeover relay control
Q506 Driver Transmission/reception changeover
relay control
IC501 Extended I/O LPF control signal (Serial→Parallel)
Ref No. Use / Function Operation / Condition / Compatibility
D501 High-frequency Reflected wave detection
rectification
D502 High-frequency Forward wave detection
rectification
D503
Surge absorption Transmission/reception changeover
Relay (K501)
D504 Surge absorption ANT changeover relay (K502)
D505,506 Surge absorption Lightning surge protection
Display Unit (X54-3410-00)
Ref No. Use / Function Operation / Condition / Compatibility
Q1~4 Switching LCD dimmer control
Q5,6 Switching Dimmer control for key illumination
Q7 Switching 5V power supply switch
IC1,2 LCD driver
IC3 MCU Panel microcomputer
IC4,5 AND gate Buffer
IC6 AVR 5V
D1~4 LED LCD backlight
D5~9 Reverse current Key matrix
prevention
D10~13 LED LCD backlight
D14 LED Lights during transmission
D15 LED Lights during reception
D16~36 LED Backlight
D37 Reset circuit
TX-RX Unit (X57-663X-XX) (A/2)
Ref No. Use / Function Operation / Condition / Compatibility
Q1 Crystal oscillator Crystal oscillation circuit (15.6MHz)
circuit
Q2 Amplifier IC1-CLK input amplifier
Q3 Buffer 31.2MHz buffer
Q4 Buffer 15.6MHz buffer
Q5 Doubler 15.6MHz x 2
Q6 Amplifier IC2-CLK input amplifier
Q7 Buffer DDS output buffer
Q8 Doubler 31.2MHz x 2
Q9 Amplifier Differential amplifier
Q10 Buffer DDS output buffer
Q11 Buffer Impedance converter
COMPONENTS DESCRIPTION

TS-480HX/480SAT
17
Ref No. Use / Function Operation / Condition / Compatibility
Q12 Doubler 31.2MHz x 2
Q13 Switching LO1 filter cutoff changeover control
Q14 Amplifier PLL-Fin amplifier
Q15 Amplifier LO1 amplifier
Q16 Switching NFMT signal
Q17 Ripple filter Filter for VCO power supply
Q18 Switching Loop filter time constant changeover switch
Q19 Mute switch Mutes FM modulation input
Q131 Inverter SQC
Q132 Switching RL output switch
Q133 Amplifier ANI/ANO signal amplifier, Amplitude limit
Q134 Switching Relay (K131) control
Q135 Switching RL output switch control
Q136 Inverter PKS signal
Q137 Inverter RTK signal
Q138 Inverter SS signal
Q201,202 AVR Panel power supply
Q203 Switching IC203 (RS-232C) power supply control
Q204 Switching Power supply voltage protection
Q205 Inverter
Q207 Switching 5C power supply switch
Q451 VCO1 Oscillation FET
Q452 VCO2 Oscillation FET
Q453,454 Switching VCO select switch
Q455 Amplifier VCO output amplifier
Q456 VCO3 Oscillation FET
Q457 Switching VCO select switch
Q501 Amplifier NB circuit input
Q502 Differential NB IF amplifier
amplifier
Q503 Amplifier NB AGC control amplifier
Q504 Amplifier NB IF amplifier
Q505 Switching Audio mute signal is generated
Q506 Buffer NB IF
Q507 Switching Audio mute signal is generated
Q508 Buffer NB input buffer
Q551 AGC amplifier AGC amplifier for receiving second IF
Q552 AGC amplifier AGC voltage control
Q553 Switching AGC-OFF switch
Q554 AGC amplifier AGC amplifier for receiving second IF
Q556 Amplifier IF amplifier for AM/AGC
Ref No. Use / Function Operation / Condition / Compatibility
Q557 Buffer Output buffer for AM detection signal
Q558 Amplifier Output amplifier for SSB/CW detection signal
Q559 Switching IF mute signal
Q560 Switching Option filter insertion loss correction switch
Q561,562 Switching IF amplifier mute switch
Q563 Switching ON while receiving in FM mode
Q621 Amplifier Output amplifier of SSB/CW modulator
Q622 AVR Power supply of SSB/CW modulator
Q623 Buffer CAR input buffer of SSB/CW modulator
Q624 AVR Power supply of SSB/CW modulator
Q625 Amplifier Modulation input of SSB/CW modulator
Q681 Switching CKY control
Q682 Switching TXB power supply generation switch
Q683 Switching CKY control
Q684,685 Switching RXB power supply generation switch
Q686 Switching AGC voltage charge switch control
Q731 Switching For meter
Q732 Switching FMB
Q733 Switching AMB/SCB
Q734 Switching AF mute switch
Q735 Ripple filter For audio amplifier power supply
Q737 Switching Audio output relay changeover control
Q803 Switching ALC time constant changeover switch
Q805 Switching AGC voltage charge switch control
Q806 Over drive
protection
Q807 Switching
IC1 DDS LO1-PLL reference signal is generated
IC2 DDS CAR generation
IC3 PLL LO1 control
IC201 Multiplexer Input signal changeover for entering it
into the A/D port of MCU (IC204)
IC202 EEPROM
IC203 Level converter RS-232C level and 5 V conversion
IC204 MCU Main microcomputer
IC205 Buffer IC Voltage conversion: 3V→5V
IC207 Buffer IC Voltage conversion: 5V→3V
IC208 Buffer IC Voltage conversion: 3V→5V
IC209 Buffer IC Voltage conversion: 5V→3V
IC210,211 Reset IC
IC212 A/D Electrical volume, Control signal is generated
COMPONENTS DESCRIPTION

TS-480HX/480SAT
18
Ref No. Use / Function Operation / Condition / Compatibility
IC213 3.3V AVR
IC214 Filter amplifier CODEC output signal
IC215 3.3V AVR DSP power supply
IC216 1.8V AVR DSP power supply
IC217 CODEC
IC218 Anti-aliasing filter CODEC input signal
IC219 Analog switch
IC220 DSP
IC221 MIC amplifier
IC222 Buffer
IC223 Inverter
IC224 Amplifier RX signal amplifier, Reference voltage
generation
IC225,226 Buffer IC Voltage conversion: 3V→5V
IC227 Buffer
IC551 FM IC FM detection
IC552 Analog switch AGC/ALC voltage changeover
IC553 Mixer IC SSB/ CW demodulator
IC554 Amplifier FM S-meter voltage amplifier
IC621 Mixer IC SSB/ CW transmission modulator
IC681 D/A Ao1: NBL/MOB
Ao2: CAR-LEVEL
Ao3: IFGC
Ao4: AGC-REF
Ao5: PGC
Ao6: POC
Ao7: VREF
Vo8: PRO
IC682 Analog switch AGC time constant changeover,
S-meter changeover
IC683 OP amplifier Buffer for S-meter
IC684 Analog switch NBL changeover switch
IC685 Analog switch AGC voltage charge
IC695 5V AVR
IC731 Shift register Q0: Low when SSB/CW/FSK mode is
selected.
Q1: Low when AM mode is selected.
Q2: Low when FM mode is selected.
Q3: Hi when the 270Hz option filter is
selected .
Ref No. Use / Function Operation / Condition / Compatibility
Q4: Hi when the 1.8kHz option filter is
selected.
Q5: Hi when AGC is slow.
Q6: Hi when AGC is OFF.
Q7: Low when the 6kHz filter is selected.
Q8: Low when the 2.4kHz filter is selected.
Q9: Low when option filter 1 is selected.
Q10: Low when option filter 2 is selected.
Q11: Low when receiving in FM mode.
IC732 OP amplifier Buffer/ amplifier for meter
IC733 Analog switch Reception detection output changeover
IC734 AF AMP
IC801 OP amplifier Power supply voltage protection
IC802 OP amplifier ALC protection
D1 Variable For FM phase modulation
capacitance diode
D2,3 Switching LO1 filter cutoff changeover
D4 Reverse current
prevention
D131 Limiter SQC over input protection
D132 Limiter ANI amplitude limit
D133 Limiter SS over input protection
D134 Limiter ANI amplitude limit
D135 Limiter RTK over input protection
D136 Surge absorption Relay (K131)
D137 Limiter Over input protection
D138 Reverse current
prevention
D139 Limiter Over input protection
D202 Poly-switch Current limit
D203,204 Limiter Over input protection
D205 Reverse current
prevention
D206 10V Zener Panel power supply reference voltage
diode generation
D207 Limiter Over input protection
D208 Reverse current
prevention
D210 Reverse current
prevention
D211 Limiter Over input protection
COMPONENTS DESCRIPTION

TS-480HX/480SAT
19
Ref No. Use / Function Operation / Condition / Compatibility
D212 18V Zener diode Voltage shift
D213 Reverse current
prevention
D351~354 Limiter Over input protection
D355,356 Reverse current
prevention
D357 Poly-switch Current limit
D358,359 Reverse current
prevention
D360 Poly-switch Current limit
D451,452 Varicap VCO oscillation frequency variance
D453 Switching ON when VCO1 is selected.
D454 Switching ON when VCO2 is selected.
D455 Varicap VCO oscillation frequency variance
D456 Switching ON when VCO3 is selected.
D501 Rectification NB voltage generation
D551 PIN diode IF gain control (IFGC)
D552 Rectification AGC control voltage generation
D555 Rectification AM detection
D557~559 Reverse current
prevention
D621,622 Voltage shift Reference voltage generation of TX
modulator power supply
D623 Temperature
compensation
D624 Reverse current
prevention
D625 Temperature
compensation
D681~683 Reverse current
prevention
D733~735 Reverse current
prevention
D736 Surge absorption Relay (K731)
D801 5.1V Zener diode
D802 Reverse current
prevention
D804 Voltage shift External ALC voltage
D805~808 Reverse current
prevention
D809 Limiter Over voltage protection
Ref No. Use / Function Operation / Condition / Compatibility
D810 Voltage shift
D811~813 Reverse current
prevention
D816,817 Reverse current
prevention
D818,819 Temperature
compensation
TX-RX Unit (X57-663X-XX) (B/2)
Ref No. Use / Function Operation / Condition / Compatibility
Q901 Amplifier 10.695MHz IF amplifier (AGC/ALC amplifier)
Q902 Switching Q901 mute switch (Mute when ON)
Q903 Switching TXB discharge switch (ON during
transmission)
Q971 Amplifier 10.695 MHz IF amplifier for receiving
D901 Attenuator IFGC voltage control
D902 Switching ON during transmission
D903 Attenuator IFGC voltage control
D904 Switching ON during reception
D905 Reverse current
prevention
D906 Switching ON during reception
D931 Switching ON when SSB mode is selected.
D932 Switching 1/2: ON when FM mode is selected.
2/2: ON when AM mode is selected.
D933 Switching ON when option filter is selected.
D934 Switching ON when AM mode is selected.
D935 Switching ON when option filter is selected.
D936 Switching ON when SSB mode is selected.
D937 Switching ON when option filter is selected.
D938 Switching ON during transmission.
D939 Switching ON when option filter is selected.
D940 Switching ON when FM mode is selected.
D941 Switching ON when AM mode is selected.
D944,945 Limiter
Sub Unit (X58-4900-XX)
Ref No. Use / Function Operation / Condition / Compatibility
Q1,2 Amplifier Drive amplifier
D1,2 Voltage shift
COMPONENTS DESCRIPTION

TS-480HX/480SAT
20
SEMICONDUCTOR DATA
Pin No. Name I/O Function
1DRO O CODEC input (VGS-1 playback) change-
over instruction H : VGS-1 playback
2PKD O CODEC input (PKD) changeover instruc-
tion H : When PKD input is selected
3Vcc1 I Power supply voltage 3.3V
4WAIT I Bus cycle wait state request
5~8 HA0~HA3 O Address bus
9Vss1 - GND
10~13 NC -
14~17 TYP0~TYP3 IMarket code detection
18 Vss2 - GND
19~22 TYP4~TYP7 IMarket code detection
23 DASH I Electronic key dash signal L : Dash ON
24 DOT I Electronic key dot signal L : Dot ON
25 KYS I Key jack connection detection
H : Key jack connection
26 KEY I Key down signal L : Key down
27 Vss3 - GND
28 TXC O Transmission power supply instruction
H : Transmission, L : Reception
29 CKY O Transmission power output instruction
H : Transmission output
30 ABK O ABK signal H : AF blanking
31 BEEP O Beep pattern instruction H : Beep output
32 DRES O DSP reset output L→H : Reset
33 MIC O CODEC input (MIC) changeover instruction
H : When MIC input is selected
34 VOS O Voice output changeover instruction
H : Voice output
35 SSR I PTT transmission instruction
H : PTT transmission, L : Reception
36 PKSR I Packet transmission/
Cross-band transmission instruction
Normal H : Transmission, L : Reception
Cross-band H : Reception, L : Transmission
37 STPC I Interrupt for returning from sleep mode
(PC) L→H : Interrupt
38 STPA I Interrupt for returning from sleep mode
(Panal) H→L : Interrupt
39 Vcc2 I Power supply voltage 3.3V
40 TYPX I Function detection 1
41 BOVR I Over voltage detection interrupt
H→L : Interrupt
Pin No. Name I/O Function
42 BKC I Reduced voltage detection interrupt
H→L : Interrupt
43 SPS I External speaker detection signal input
H : When Speaker jack is connected
44 DADT O D/A (X57 IC212) exclusive data
45 DACK O D/A (X57 IC212) exclusive clock
46 IEN3 O D/A (X57 IC212) exclusive enable
47 Vss4 - GND
48 LNA1 O LINEA control signal 1 (relay)
H : Relay operation selection
49 LNA2 O LINEA control signal 2 (RL)
H : RL output selection
50 PKP O Cross-band repeater operation instruction
L : Cross-band selection
51 SQC O Squelch signal H : Open, L : Close
52~55 HD0~HD3 OData bus
56 Vss5 - GND
57~60 HD4~HD7 OData bus
61 Vcc3 I Power supply voltage 3.3V
62 TXD0 O Panel microcomputer communication
data output
63 TXD1 O The data output to PC/IF
64 RXD0 I Panel microcomputer communication
data input
65 RXD1 I Data input from PC/IF
66 PHSW O External / internal speaker changeover
L : Internal speaker
67 AMU O AF mute signal (Power ON/OFF)
H : AF blanking
68 TCS O AT tuning status instruction
H : During AT tuning
69 STS O RS-232 IC start instruction
H : RS-232 power on
70 RTS1 O The UART operation instruction output
to PC/IF
71 Vss6 - GND
72 CTS1 I The UART operation instruction input
from PC/IF
73 BUSY I VGS-1 busy status detection H : Busy
VGS-1 connection detection (Power ON)
74 PLAY I VGS-1 playback detection
L →H : Playback start
75 NC I
Main Microcomputer : HD64F2338VFC25 (TX-RX Unit IC204)