Icom IC-R3 Service Manual

SERVICE
MANUAL

COMMUNICATIONS RECEIVER

6-9-16, Kamihigashi, Hirano-ku, Osaka 547-0002, Japan
Phone : [phone]
Fax : [phone]
URL : http://www.icom.co.jp/world/index.html

Communication Equipment
Himmelgeister Str. 100, D-40225 Düsseldorf, Germany
Phone: [phone] Fax : [phone]
URL : http://www.icomeurope.com

Unit 9, Sea St., Herne Bay, Kent, CT6 8LD, U.K.
Phone: [phone] Fax : [phone]
URL : http://www.icomuk.co.uk

Zac de la Plaine, Rue Brindejonc des Moulinais
BP 5804, 31505 Toulouse Cedex, France
Phone: [phone] Fax : [phone]
URL : http://www.icom-france.com

Crta. de Gracia a Manresa Km. 14,750
08190 Sant Cugat del Valles Barcelona, SPAIN
Phone: [phone] Fax : [phone]
URL : http://www.icomspain.com

<

Corporate Headquarters

>

2380 116th Avenue N.E., Bellevue, WA 98004, U.S.A.
Phone: [phone] Fax : [phone]
URL : http://www.icomamerica.com

<

Customer Service

>

Phone: [phone]

Glenwood Centre #150-6165
Highway 17 Delta, B.C., V4K 5B8, Canada
Phone: [phone] Fax : [phone]
URL : http://www.icomcanada.com

A.C.N. 006 092 575
290-294 Albert Street, Brunswick, Victoria, 3056, Australia
Phone: [phone] Fax : [phone]
URL : http://www.icom.net.au

6F No. 68, Sec. 1 Cheng-Teh Road, Taipei, Taiwan, R.O.C.
Phone: [phone] Fax : [phone]

INTRODUCTION

DANGER

ORDERING PARTS

REPAIR NOTES

This service manual describes the latest service information
for the

IC-R3

at the time of publication.

NEVER connect the receiver to an AC outlet or to a DC power
supply that uses more than 16 V. Such a connection could
cause a fire hazard and/or electric shock.

DO NOT expose the receiver to rain, snow or any liquids.
DO NOT reverse the polarities of the power supply when con-

necting the receiver.
DO NOT apply an RF signal of more than 20 dBm (100mW)

to the antenna connector. This could damage the receiver’s
front end.

Be sure to include the following four points when ordering
replacement parts:

1. 10-digit order numbers

2. Component part number and name

3. Equipment model name and unit name

4. Quantity required
<SAMPLE ORDER>

1140008440 S.IC AK93C10A IC-R3 LOGIC UNIT 5 pieces
8810009560 Screw BTM2 x 6 ZK IC-R3 Chassis 10 pieces

Addresses are provided on the inside back cover for your
convenience.

1. Make sure a problem is internal before disassembling the receiver.

2. DO NOT open the receiver until the receiver is disconnected from its power source.

3. DO NOT force any of the variable components. Turn them slowly and smoothly.

4. DO NOT short any circuits or electronic parts. An insulated turning tool MUST be used for all adjustments.

5. DO NOT keep power ON for a long time when the receiver is defective.

6. READ the instructions of test equipment thoroughly before connecting equipment to the receiver.

To upgrade quality, all electrical or mechanical parts and
internal circuits are subject to change without notice or oblig­ation.

TABLE OF CONTENTS

SECTION 1 SPECIFICATIONS

SECTION 2 INSIDE VIEWS

SECTION 3 DISASSEMBLY INSTRUCTIONS

SECTION 4 CIRCUIT DESCRIPTION

4 - 1 RECEIVER CIRCUITS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 - 1

4 - 2 PLL CRICUITS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 - 5

4 - 3 FM-TV CIRCUIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 - 6

4 - 4 POWER SUPPLY CIRCUITS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 - 8

4 - 5 PORT ALLOCATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 - 8

SECTION 5 ADJUSTMENT PROCEDURES

5 - 1 PREPARATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 - 1

5 - 2 PLL ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 - 3

5 - 3 RECEIVER ADJUSTMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 - 5

5 - 4 TFT LCD AND FM-TV UNITADJUSTMENT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 - 7

SECTION 6 PARTS LIST

SECTION 7 MECHANICAL PARTS AND DISASSEMBLY

SECTION 8 SEMI-CONDUCTOR INFORMATION

SECTION 9 BOARD LAYOUTS

9 - 1 VCO AND RF-B UNITS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 - 1

9 - 2 FM-TV UNIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 - 3

9 - 3 LOGIC UNIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 - 5

9 - 4 RF UNIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 - 7

SECTION 10 BC-135 OPTIONAL DESKTOP CHARGER INFORMATION

10 - 1 PARTS LIST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 - 1

10 - 2 DISASSEMBLY INFORMATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 - 1

10 - 3 VOLTAGE DIAGRAM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 - 2

10 - 4 BOARD LAYOUTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 - 3

SECTION 11 BLOCK DIAGRAM

SECTION 12 VOLTAGE DIAGRAM

12 - 1 VCO UNIT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 - 1

12 - 2 RF-B UNIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 - 2

12 - 3 FM-TV UNIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 - 3

12 - 4 LOGIC UNIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 - 4

12 - 5 RF UNIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 - 5

M GENERAL

• Frequency range : 0.495–2450.095 MHz

• Mode : F3, A3, C3F (TV)

• No. of memory channel : 450 channels

• Frequency stability : ±6 ppm max.
(–10˚C to +50˚)

• Tuning steps : 5, 6.25, 10, 12.5, 15, 20,
25, 30, 50, and 100 kHz

• Anntena connector : BNC (50 Ω)

• Power supply requirement :

• Polarity : Negative ground

• Frequency resolution : 5 kHz, 6.25 kHz

• Current drain (at 4.5 V) : (Typical)

• Usable temperature range : –10˚C to +60˚C
( –14˚F to +140˚F)

• Dimensions :

61(W) × 120(H) × 32.9(D) mm;

(projections not included)

213⁄32(W) × 423⁄32(H) × 19⁄32(D) in

• Weight

(w/ antenna and battery)

: 300 (g); 10.6 (oz)

• External SP connector : 3-conductor 3.5(d) mm
(

1

⁄8”)/8 Ω

• Video/Audio OUT connector : 3-conductor 3.5(d) mm
(

1

⁄8”)/8 Ω

M RECEIVER

• Receiver system : Tripple super heterodyne

• Intermediate frequencies : (Unit; MHz)

*

1

30–799.995 MHz and 1321–2099.995 MHz range

*2800–1320.995 MHz and 2100–2450.095 MHz range

• Converter frequency : 1291, 1320 or 1351 MHz
(More than 1150 MHz)

• Sensitivity* : (except spurious points)

*

FM and WFM are measured at 12 dB SINAD; AM is measured
at 10 dB S/N.

• Squelch Sensitivity :

• Selectivity :
AM / FM more than 12 kHz/–6dB

less than 30 kHz/–50 dB

WFM more than 150 kHz/–6 dB

• Audio output power : 100 mW typical at 10%

distortion with an 8 Ω load

• Audio output impedance : 8 Ω

1 - 1

SECTION 1 SPECIFICATIONS

All stated specifications are subject to change without notice or obligation.

Frequency (MHz)

0.495 – 1.625

1.625 – 5.0

5.0 – 30.0

30.0 – 76.0

76.0 – 108.0

108.0 – 118.0

118.0 – 136.0

136.0 – 175.0

175.0 – 222.0

222.0 – 330.0

330.0 – 470.0

470.0 – 770.0

770.0 – 800.0

800.0 – 1300.0

1300.0 – 2000.0

2000.0 – 2300.0

2300.0 – 2450.095

FM

—

0.56 µV

0.4 µV

0.56 µV

0.79 µV
1 µV

1.4 µV

2.5 µV

WFM

—

1.8 µV

—

1.8 µV
—

2.5 µV

—

AM

2.5 µV

1.8 µV

—

1.8 µV
—

1.8 µV

—

Battery

3

× alkaline cell

3

× AA(R6) Ni-Cd

1

× Li-ion

External DC supply

Voltage

DC 4.5 V
DC 3.6 V
DC 3.7 V

DC 3.6–6.3 V

Receiving condition

Rated audio

Standby

Power saved (1:4)

TV reception

LCD lighting

TV sound receiving

Except converter

210 mA
140 mA

65 mA

730 mA
210 mA

Converter area

250 mA
180 mA

75 mA

780 mA
250 mA

Frequency (MHz)

0.495 – 1.625

1.625 – 5.0

5.0 – 30.0

30.0 – 76.0

76.0 – 108.0

108.0 – 118.0

118.0 – 136.0

136.0 – 175.0

175.0 – 222.0

222.0 – 330.0

330.0 – 470.0

470.0 – 770.0

770.0 – 800.0

800.0 – 1300.0

1300.0 – 2000.0

2000.0 – 2300.0

2300.0 – 2450.095

FM

—

0.56 µV

0.4 µV

0.56 µV

0.79 µV
1 µV

1.4 µV

2.5 µV

WFM

—

10.0 µV

—

10.0 µV
—

10.0 µV

—

AM

2.5 µV

1.8 µV

—

1.8 µV
—

1.8 µV

—

1ST IF
2ND IF
3RD IF

AM, FM

240.1

26.05

0.450

WFM

240.1

13.25

0.450

C3F (TV)

241.85*

1

, 238.35*

2

58.75
—

SECTION 2 INSIDE VIEWS

2 - 1

•

RF, RF-B, VCO AND FM-TV UNITS

•

LOGIC UNIT

2nd IF circuit
(FI3: FL-319)

FM-TV UNIT
([OTH-2] only])

RF-B UNIT

VCO UNIT

RF UNIT

CPU system clock
(X1: CR-613)

Power amplifier
(IC3: XC62FP3002MR)

DC-DC converter

CPU
(IC1: M38267M8L-256GP)

PLL converter circuit
(IC15: TA31056F)

IC801: MB3776APFV
Q804: 2SK2493
T1: TO-47

SECTION 3 DISASSEMBLY INSTRUCTIONS

3 - 1

•

REMOVING THE REAR PANEL

1 Unscrew 3 screws, A

.

2 Unscrew 1 screw, B

.

3 Remove the rear panel in the direction of the arrow.
4 Unplug speaker connector to separate front panel and

rear panel.

•

REMOVING THE LOGIC UNIT

1 Unscrew 1 screw, D

.

2 Remove the LOGIC unit in the direction of the arrow.

•

REMOVING THE RF UNIT

1 Remove the 1 knob and unscrew 2 nuts

.

2 Unscrew 3 screws, E, and unsolder 8 points, F.

Unsolder 1 points, H ([OTH-2] only).

3 Remove the shield plate.
4 Unsolder 3 points, G, and remove the RF unit.

Rear Panel

Speaker
connector

B

A

D

LOGIC unit

E

RF unit

Shield plate

Nuts

Knob

G

E

H

F

F

F

SECTION 4 CIRCUIT DESCRIPTION

4 - 1

4-1 RECEIVER CIRCUITS

4-1-1 RF SWITCHING CIRCUIT (RF UNIT)

(1) Below 1150 MHz

The RF signals from the antenna connector pass through
the band switching diode (D2) and an attenuator (D12, D13).
The signals are then applied to the RF circuit which sup­press out-of-band signals via the band switching diode
(D911).

(2) Above 1150 MHz

The RF signals from the antenna connector pass through
the limitter (D1), band switching diode (D909) and high-pass
filter (C932–C936, C963, C964, L911, L912, L914). The fil­tered signals are applied to the AF amplifier (IC14, pin 1),
and are then applied to the convertor circuit (IC13, pin 1).
Above 1150 MHz RF signals are mixed with “CONLO” signal
from CONV VCO circuit for convertion into below 1150 MHz
RF signals at the converter circuit (IC13). The converted sig­nals are output from IC13 (pin 6), and are then applied to the
RF circuit which suppress out-of-band signals.

4-1-2 RF CIRCUIT (RF AND RF-B UNITS)

The RF circuit amplifies the received signals within the
range of frequency coverage and filters out-of-band signals.

(1) 0.495 MHz–29.995 MHz

RF signals (0.495 MHz–29.995 MHz) from the RF switching
circuit pass through a low-pass filter (C321–C325, L81,
L82). The filtered signals are amplified at an RF amplifier
(Q3) passing through each low-pass, bandpass, high-pass
filter depending on the receiving frequency. The amplified
signals are then applied to the 1st mixer circuit (IC1) via the
band switching diode (D10).

The signals below 1.9 MHz pass through a low-pass filter
(C344–C347, L89, L90) between the band switching diode
(D4, D7), and are then applied to the RF amplifier circuit
(Q3).

The 1.9 MHz–14.995 MHz signals pass through the band
switching diode (D5) and bandpass filter (C332–C341,
L85–L88), and are then applied to the RF amplifier circuit
(Q3) via the band switching diode (D8).

The 15 MHz–29.995 MHz signals pass through the band
switching diode (D6) and high-pass filter (C326–C330, L83,
L84) and are then applied to the RF amplifier circuit (Q3) via
the band switching diode (D9).

(2) 30 MHz–224.995 MHz (RF-B UNIT)

RF signals (30 MHz–64.995 MHz, 65 MHz–107.995 MHz,
108 MHz–173.995 MHz, 174 MHz–224.995 MHz) from the
RF switching diode (RF unit; D11) are passed through the
low-pass filter (RF unit; C12–C17, L57–L59). The filtered
signals pass through the each bandpass filters and RF
amplifier depending on the receiving frequency. The signals
are then applied to the 1st mixer circuit (RF unit; IC1).

The 30 MHz–64.995 MHz signals pass through the band
switching diode (D403) and bandpass filter (D401), and are
then amplified at the RF amplifier (Q401). The amplified sig­nals pass through the bandpass filter (D402) and band
switching diode (D404).

RF CIRCUIT

ANT

ANT
SW

D909, D912

"CONLO" signal from
the CONV VCO circuit

ANT
SW

D2, D911

IC13

Below 1150 MHz RF signals

Above 1150 MHz RF signals

LPFLPF

ANT
SW

BPF

RF

D4—D9

ANT
SW

D3, D10

0.495 30 MHz

30 225 MHz

330 470 MHz

470 800 MHz

225 330 MHz,
800 1150 MHz

Q3

LPF

ANT
SW

BPF BPF

RF

D403, D404
D503, D504
D603, D604
D703, D704

ANT
SW

D11

Q401, Q501,
Q601, Q701

BPF BPF

RF

ANT
SW

D21, D24

Q7

BPF BPF

RF

ANT
SW

ANT
SW

D803, D804
D853, D854

D805

Q801, Q851

LPF

BPF

RF

ANT
SW

D33, D35, D36

Q8, Q9

1st LO

IC1

D902

D1

to the FM-TV circuit

to the 2nd mixer circuit

FM-TV UNIT

RF-B UNIT

Displayed frequency

CONVERTED RF FREQUENCY LIST

RF frequency

1150.000—1176.000

1176.005—1229.995

1230.000—1255.000

1255.005—1286.000

1286.005—1320.995

1321.000—1349.995

1350.000—1384.995

1385.000—1394.995

1395.000—1427.995

1428.000—1515.995

1516.000—1569.995

1570.000—1579.995

1580.000—1739.995

1740.000—1789.995

1790.000—1809.995

1810.000—1849.995

1850.000—2039.995

2040.000—2109.995

2110.000—2204.995

2205.000—2250.995

2251.000—2450.095

141.000—115.000

143.995—90.005

61.000—36.000

64.995—34.000

64.995—30.005

30.000—58.995

30.000—64.995

94.000—103.995

75.000—107.995

137.000—224.995

196.000—249.995

250.000—259.995

289.000—448.995

420.000—469.995

499.000—518.995

490.000—529.995

559.000—748.995

720.000—789.995

819.000—913.995

885.000—930.995

960.000—1159.095

4 - 2

The 65 MHz–107.995 MHz signals pass through the band
switching diode (D503) and bandpass filter (D501), and are
then amplified at the RF amplifier (Q501). The amplified sig­nals pass through the bandpass filter (D502) and band
switching diode (D504).

The 108 MHz–173.995 MHz signals pass through the band
switching diode (D603) and bandpass filter (D601), and are
then amplified at the RF amplifier (Q601). The amplified sig­nals pass through the bandpass filter (D602) and band
switching diode (D604).

The 174 MHz–224.995 MHz signals pass through the band
switching diode (D703) and bandpass filter (D701), and are
then amplified at the RF amplifier (Q701). The amplified sig­nal pass through the bandpass filter (D702) and band
switching diode (D704).

(3) 330 MHz–469.995 MHz

RF signals (330 MHz–469.995 MHz) from the RF switching
circuit pass through the band switching diode (D21) and a
bandpass filter (C19–C27, L2–L5, L39). The filtered signals
are amplified at an RF amplifier (Q7), and then passed
through the bandpass filter (D22, D23). The filtered signals
are then applied to the 1st mixer circuit (IC1) via the band
switching diode (D24).

(4) 470 MHz–799.995 MHz

RF signals (470 MHz–799.995 MHz) from the RF switching
circuit pass through the band switching diode (D805) and a
low-pass filter (C321–C325, L81, L82). The filtered signals
are passed through each bandpass filter and RF amplifier
depending on the receiving frequency. The amplified signals
are then applied to the 1st mixer circuit (IC1) via the band
switching diode (D804 or D854) respectively.

The 470 MHz–599.995 MHz signals pass through the band
switching diode (D803) and bandpass filter (D801), and are
then amplified at the RF amplifier (Q801). The amplified sig­nals pass through the bandpass filter (D802) and band
switching diode (D804).

The 600 MHz–799.995 MHz signals pass through the band
switching diode (D853) and bandpass filter (D851), and are
then amplified at the RF amplifier (Q851). The amplified sig­nals pass through the bandpass filter (D852) and band
switching diode (D854).

(5) 225 MHz–329.995 MHz AND 800 MHz–1149.995 MHz

RF signals (225 MHz–329.995 MHz and 800 MHz–1149.995
MHz) from the RF switching circuit pass through the band
switching diode (D33). The signals are passed through each
bandpass filter and RF amplifier depending on the receiving
frequency. The amplified signals are then applied to the 1st
mixer circuit (IC1) via the band switching diodes (D35 or
D36) respectively.

The 225 MHz–329.995 MHz signals pass through the band­pass filter (C40–C43, C395, C396, L58, L59), and are then
amplified at the RF amplifier (Q9). The amplified signals
pass through the band switching diode (D35).

The 800 MHz–1149.995 MHz signals pass through the
bandpass filter (C46–C49, C51–C54, L11–L14), and are
then amplified at the RF amplifier (Q8). The amplified sig­nals pass through the band switching diode (D36).

4-1-3 1ST MIXER CIRCUIT (RF UNIT)

The 1st mixer circuit converts the received RF signals to a
fixed frequency of the 1st IF signal with a PLL output fre­quency. By changing the PLL frequency, only the desired
frequency will pass through the bandpass filters at the next
stage of the 1st mixer.

The filtered or amplified RF signals from each RF circuit are
mixed with 1st LO signal at the 1st mixer circuit (IC1) to pro­duce each 1st IF signal depending on the receiving fre­quency. The 1st IF signal is output from pin 6, and passed
through the bandpass filter (FI904) to suppress unwanted
harmonic components. The filtered 1st IF signal is applied to
the 2nd mixer circuit.

*

1

30–799.995 MHz and 1321–2099.995 MHz range

*

2

800–1320.995 MHz and 2100–2450.095 MHz range

The 1st LO signals are generated at the 1st VCO (VCO unit;
Q22, Q23, D62) and are applied to the 1st mixer (IC1, pin 3)
directly or passed through the doubler circuit (Q26) after
being amplified at the buffer amplifier (VCO unit; IC4).

1ST IF

FM, AM, WFM

240.1 MHz

C3F (TV)

241.85*

1

, 238.35*2 MHz

1ST MIXER CIRCUIT (RF UNIT)

"RFO" signals from
the each front-end circuit

"1st VCO" signal from
the 1st VCO circuit (VCO unit)

"R3V" signal from
the LOGIC unit

"1st IF" signal to
the 2nd mixer circuit

"1st IF" signal to
the FM-TV unit

1st mixer IC (IC1)

C153

R255

R256

R257

1

2

3

6

5

4

C152

C70

C234

4 - 3

4-1-4 1ST IF AND 2ND MIXER CIRCUITS (RF UNIT)

The 2nd mixer circuit converts the 1st IF signal to a 2nd IF
signal.

The filtered each 1st IF signal from the bandpass filter are
mixed with the 2nd LO signal at the 2nd mixer circuit (IC10,
pin 1) to produce each 2nd IF signal depending on the
receiving frequency.

In AM and FM mode, the 2nd IF signal (26.5 MHz) passes
through the band switching diode (D71) and bandpass filter
(FI3). The filtered signals are then amplified at the 2nd IF
amplifier (Q41), and are applied to the demodulator circuit.

In WFM mode, the 2nd IF signal (13.25 MHz) passes
through the band switching diode (D72) and bandpass filter
(FI4). The filtered signal is then amplified at the 2nd IF
amplifier (Q41), and is applied to the demodulator circuit.

In TV mode, the 2nd IF signal (58.75 MHz) passes through
the band switching diode (D901) and is then applied to the
2nd IF amplifier (Q857). The amplified signal passes
through the bandpass filter (FI901), and is applied to the
demodulator circuit.

4-1-5 DEMODULATOR CIRCUITS (RF UNIT)

The demodulator circuit converts the 2nd IF signal into AF
signals or video signals.

(1) AM, FM AND WFM MODE

The each 2nd IF signals from the 2nd IF amplifier (Q41) are
applied to the 3rd mixer section of the FM IF IC (IC2, pin 16)
and are then mixed with the 3rd LO signal for conversion
into a 450 kHz 3rd IF signal.

IC2 contains the 3rd mixer, limiter amplifier, quadrature
detector and S-meter detector, etc. A frequency from the
PLL reference oscillator (VCO unit; IC3) is used for the 3rd
LO signal (12.80 MHz).

• AM MODE

The 3rd IF signal is output from FM IF IC (IC2, pin 3) and
passes through the ceramic bandpass filter (FI2). The fil­tered signal is applied to the AM detector circuit (Q44, Q45)
to convert into AF signals, and the signals are applied to the
AF circuit (LOGIC unit).

• FM MODE

The 3rd IF signal is output from FM IF IC (IC2, pin 3) and
passes through the ceramic bandpass filter (FI2). The fil­tered signal is fed back and amplified at the limiter amplifier
section (pin 5), then demodulated AF signals at the quadra­ture detector section (pins 10, 11) with detector coil (L21).
The demodulated AF signals are output from pin 9 and are
applied to the AF circuit (LOGIC unit).

• WFM MODE

The 3rd IF signal from the 3rd mixer bypasses the ceramic
filter (FI2) and fed back to the limiter amplifier section (pin 5).
The amplified signal is demodulated at the quadrature
detector section (pins 10, 11) with detector coil (L21). The
AF signals are output from pin 9 and are applied to the AF
circuit (LOGIC unit).

By connecting R55 to R54 in parallel, the output character­istics of pin 12, “RSSI”, change gradually. Therefore, the FM
IF IC can detect WFM components.

3RD IF AND DEMODULATOR CIRCUITS (RF UNIT)

Mixer

16

Limiter
amp.

3rd IF filter

450 kHz

RSSI

IC2 TA31136FN

13

2nd IF signal from the
IF amplifier (RF unit; Q41)

"RSSI" signal to the CPU
(Logic unit; IC11, pin 7)

11109

875 32

Active
filter

FI2

Noise

detector

FM

detector

Noise
comp.

"SDET" signal to the CPU
(Logic unit; IC11, pin 12)

12

C106

C108 C109

C111

R61

R59

R60

WFM

RX

"FMAF" or "AMAF" signal
to the AM/FM switch circuit
(LOGIC unit; D15, D18)

3rd

Q42

"3rd LO" signal from
IC3, pin 2 (VCO unit)

C112

R57

C992

R54

R55

2

Q121

D121

D122

C114

C115

D75 D76

R84

R56

C113

L21

4 - 4

(2) TV MODE

The amplifed signals at the 2nd IF amplifier (Q857) are
applied to the bandpass filter (FI901). The filtered signals
are applied to the TV IF IC (IC901) as audio IF signal and
the video IF signal, separately.

IC901 is the video/audio detector IC of the PLL sprit type,
which contains the video IF amplifier, PLL video detector,
voice IF detector, IF and RF AGC, etc.

The audio IF signal from FI901 (pin 3) is applied to the TV IF
IC (IC901, pin 9) as the “SIF” signal, and is amplified and
phase detected in the IC. The phase detected signal is out­put from pin 15, and is fed back to pin 13 via FI902. The fil­tered signal is applied to the limitter amplifier section and
FM detector section in the TV IF IC.

The demodulated AF signals are output from pin 12 and are
applied to the AF circuit (LOGIC unit).

The video IF signal from FI901 (pin 4, 5) is applied to the TV
IF IC (IC901, pin 4, 5) as “VIF” signal, and is then amplified
at the video IF amplifier in the TV IF IC. The amplified signal
is compared with the VCO frequency (L902, C906), and is
then applied to the phase detector section in the TV IF IC.
The detected signal is output from pin 22 as the video sig­nal, and then passed through the bandpass filter (FI905).
The filtered signal is amplified at Q854, and applied to the
buffer amplifier (Q855). The amplified signal is applied to the
TFT LCD circuit (LOGIC unit).

4-1-6 AF AMPLIFIER CIRCUIT (LOGIC UNIT)

The AF amplifier circuit amplifies the demodulated AF sig­nals to drive a speaker.

While in FM and TV mode, AF signals (“FMAF” signal) from
the demodulator circuit (RF unit) are passed through the de­emphasis circuit (R118, C66, C68) with frequency charac­teristics of –6 dB/octave, and are then applied to the pre­amplifier (Q31) via the bandpass filter (Q30).

While in AM mode, AF signals (“AMAF” signal) are pass
through the bandpass filter (Q30) and are then applied to the
pre-amplifier (Q31).

While in WFM mode, AF signals (“WFM” signal) are applied
to the pre-amplifier (Q31) directly.

The pre-amplified AF signals pass through the AF mute cir­cuit (Q37) and are then applied to the electronic volume con­trol circuit (IC14, pin 6). The level controlled AF signals are
output from pin 7 and applied to the AF power amplifier
(IC15, pin 1) via the buffer amplifier (Q36). The power ampli­fied AF signals are applied to the internal speaker via the
[EXT SP] jack.

The electronic volume control circuit controls AF gain, there­fore, the AF output level is according to the [VOL] setting
and also the squelch conditions. The AF mute and electron­ic volume control circuits are controlled by CPU (IC11) via
each “AMUTE” and “VRC” signal lines.

When connecting [A/V OUT] jack (RF unit; J3) on TV mode,
AF signals from demodulator circuit (RF unit; IC901, pin 12)
are applied to the [A/V OUT] jack directly.

On AM, FM, WFM mode, AF signals from demodulator cir­cuit (RF unit; IC2, pin 9) are applied to the RF amplifier (FM­TV unit; Q71) via J5 (pin 1) on RF unit. The amplified signals
are applied to the [A/V OUT] jack via the J7 (pin 3).

4-1-7 TFT LCD CIRCUIT (LOGIC UNIT)

The amplified video signal from Q855 on MAIN unit is ampli­fied at the buffer amplifier (Q903, Q904), and is then applied
to the OSD (On Screen Display) IC (IC902, pin 10). The
OSD IC produces LCD screen display data, and then out­puts video signals to the TFT driver (IC901).

The TFT driver contains the procesing of RGB signal circuit,
color control circuit, etc. The TFT driver controls the TFT
LCD (DS4) using the video signals from the OSC IC.

4-1-8 SQUELCH CIRCUIT (LOGIC AND RF UNITS)

• NOISE SQUELCH

The noise squelch circuit cuts out AF signals when no RF
signals are received. By detecting noise components in the
AF signals, the squelch circuit switches the AF mute switch.

TV DEMODULATOR CIRCUIT

D901

D914

Q857

IC901

IC902

FI902 FI905 Q854 Q855

Q903,
Q904

Q854

Buff.

Amp.

IF
amp.

BPF

BPF

Buff.

Buff.

TV IF IC

BPF

A/V OUT (RF unit; J3)

"VIDEO" signal
to the TFT driver circuit (IC901)

2nd IF signal from the
2nd mixer circuit (IC10, pin 6)

"FMAF" signal
to the AF amplifier circuit

audio signal

AF signal from the
FM IF IC (IC2, pin 9)

video signal

OSD

RF UNIT

LOGIC UNIT

4 - 5

A portion of the AF signals from the FM IF IC (RF unit; IC2,
pin 9) are applied to the active filter section (IC2, pin 8). The
active filter section amplifies and filters noise components.
The filtered signals are applied to the noise detector section
and output from pin 13 as the “SDET” signal.

The “SDET” signal from IC2 (pin 13) is applied to the CPU
(LOGIC unit; IC11, pin 12) directly. The CPU analyzes the
noise condition and outputs the “AMUTE” signal to the AF
mute switch (Q37).

Even when the squelch is closed, the AF mute switch (Q37)
opens at the moment of emitting beep tones.

• TONE SQUELCH

The tone squelch circuit detects AF signals and opens the
squelch only when receiving a signal containing a matching
subaudible tone (CTCSS). When tone squelch is in use, and
a signal with a mismatched or no subaudible tone is
received, the tone squelch circuit mutes the AF signals even
when noise squelch is open.

A portion of the AF signals from the FM IF IC (RF unit; IC2,
pin 9) passes through the low-pass filter (LOGIC unit; IC9)
via the “FMAF” signal to remove AF (voice) signals and
passes through the tone filter (LOGIC unit; IC9, Q8). The fil­tered signal is applied to the CTCSS decoder inside CPU
(LOGIC unit; IC11, pin 8) via the “RTONE” line to control the
AF mute switch.

4-2 PLL CIRCUITS

4-2-1 PLL CIRCUIT (VCO UNIT)

A PLL circuit provides stable oscillation of the receive
1st/2nd LO frequencies. The PLL circuit compares the
phase of the divided VCO frequency to the reference fre­quency. The PLL output frequency is controlled by the divid­ed ratio (N-data) of a programmable divider.

PLL CIRCUIT

Shift register

Prescaler

Phase
detector

Loop

filter

Loop

filter

Programmable
counter

Programmable
divider

X1

12.8 MHz

Buff.

Q25

D63D64

D65D67

D66D68

IC4

3
4
5

PSTB

IC3 (PLL IC)

PCK
PDA

16

13

17

19

1st VCO

Q22,
Q23,

D62

Q31,
Q32

8

Loop

filter

Q870,
Q871

Buff.

Q853

D41

2

"2nd LO" signal to the 2nd mixer
circuit (IC10, pin 3)

"1st LO" signal to the 1st mixer
circuit (IC1, pin 3)

"CONLO" signal to the converter
mixer circuit (IC13, pin 3)

2nd VCO

Q34, D202

Converter VCO

Q861, D913

Amp.

Amp.

Buff.

Q862RFQ863

LPF

RF

Q864

Q874

2

2

VXO

IC15

(Converter PLL IC)

RF UNIT

VCO UNIT

3
4
5

PCK
PDA
PSTB

1

6

"REF" signal to the FM IF IC
(IC2, pin 2)

10

BPF

4 - 6

An oscillated signal from the 1st VCO passes thorough the
buffer amplifiers (IC4, Q25), is applied to the PLL IC (IC3,
pin 19) and is prescaled in the PLL IC based on the divided
ratio (N-data). The PLL IC detects the out-of-step phase
using the reference frequency and outputs it from pin 13.
The output signal is passed through the loop filter (Q31,
Q32) and is then applied to the 1st VCO circuit as the lock
voltage.

4-2-2 CONVERTER PLL CIRCUIT

(RF AND VCO UNITS)

An oscillated signal from the converter VCO is applied to the
buffer and RF amplifiers (Q862, Q863). The amplified signal
passes through the bandpass filter (VCO unit; C972–C979,
C981, C982, L921–L924), and is then amplified at the RF
amplifier (VCO unit; Q864) and LO amplifier (RF unit;
Q874). The amplified signal is applied to the converter PLL
IC (RF unit; IC15, pin 1) and is prescaled in the converter
PLL IC based on the divided ratio (N-data). The converter
PLL IC detects the out-of-step phase using the reference
frequency and outputs it from pin 10. The output signal is
passed through the loop filter (RF unit; C956–C958, R945,
R946) and is then applied to the converter VCO circuit as
the lock voltage.

4-2-3 REFERENCE OSCILLATOR CIRCUIT

(VCO UNIT)

The reference oscillator circuit (X1, IC3) generates a 12.8
MHz reference frequency which is stabilized within the tem­perature range –10˚C (+14˚F) to +60˚C (+140˚F). The refer­ence frequency is applied to the PLL IC (IC3, pin 16) and the
signal is output from pin 17, and is then applied to the con­verter PLL IC (RF unit; IC15, pin 6) and FM IF IC (RF unit;
IC2, pin 2).

4-2-4 1ST VCO CIRCUIT (VCO UNIT)

The oscillated signal is applied to the buffer amplifier (IC4).
The amplified signal is applied to the 1st mixer circuit (RF
unit; IC1, pin 3) via the RX LO swtich circuit (RF unit;
D63–D68) and doubler circuit (RF unit; Q25).

The 1st VCO circuit (Q22, Q23, D62) oscillates 240.6
MHz–359.9475 MHz (Low) and 348.1 MHz–520.0475 MHz
(High) respectively by switching the SHIFT switch (Q21,
D61).

A portion of the signal from IC4 is amplified at the buffer
amplifier (Q25) and is then fed back to the PLL IC (IC3, pin

19) as the comparison signal.

4-2-5 2ND VCO CIRCUIT (VCO UNIT)

The 2nd LO circuit generates the 2nd LO frequencies, and
the signals are applied to the 2nd mixer circuit.

The 2nd VCO circuit (Q34, D202) oscillates 183.1–297.1
MHz signal. The oscillated signal is applied to the 2nd mixer
(RF unit; IC10, pin 3), and is then mixed with the 1st IF sig­nal.

An oscillated signal from the 2nd VCO is applied to the
buffer amplifier (Q853). The amplified signal passes through
the low-pass filter (C154, C250–C252, L69), and is applied
to the PLL IC (IC3, pin 2), and is then output from pin 8.

4-2-6 CONVERTER VCO CIRCUIT (VCO UNIT)

The converter LO circuit generates the converter LO fre­quencies, and the signals are applied to the converter mixer
circuit.

The converter VCO circuit (Q816, D913) oscillates

645.5–675.5 MHz signal. The oscillated signal is applied to
the buffer amplifier (Q862), and is then amplified at the RF
amplifier (Q863) to double the oscillating frequency. The
1291–1351 MHz signal is applied to the RF amplifier (Q864)
via the bandpass filter (C972–C979, C981, C982,
L921–L924). The amplified signal is applied to the converter
mixer (RF unit; IC13, pin 3), and is then mixed with the
above 1150 MHz RF signal.

An oscillated signal from the converter VCO is applied to the
LO amplifier (RF unit; Q874). The amplified signal is applied
to the converter PLL IC (RF unit; IC15, pin 1).

4-3 FM-TV CIRCUIT

4-3-1 FM-TV CIRCUIT (FM-TV UNIT)

([OTH-2] only includes this unit)

The 426.05 MHz 1st IF signal from the 1st mixer (RF unit;
IC1, pin 6) passes through the IF switching diode (D1) via
the J6 on the RF unit. The signal is passed through the
bandpass filter (FI1) to suppress unwanted signal, and then
applied to the IF amplifier (IC1, pin 4). The amplified signal
is applied to the FM-TV detector IC (IC2, pins 24 and 25).
The FM-TV detector IC contains the AGC amplifier, loop
amplifier, video amplifier, etc. The video and audio signals
are output from the FM-TV detector separately.

• VIDEO SIGNAL

The detected video signal from the FM-TV IC (IC1) is ampli­fied at the buffer amplifier (Q21), and then applied to the
amplifier (IC21, pin 1 and 8). The amplified signal is applied
to the video selector IC (IC22, pin 1 and 3) to obtain 6 dB
amplification. The amplified signal is output from the video
selector IC (pin 7), and is then applied to the buffer amplifi­er (RF unit; Q855) via the “VIDEO” signal. The amplified sig­nal is applied to the TFT LCD circuit on the LOGIC unit.

• AUDIO SIGNAL

The oscillator (Q51, C53–C55, C57, D51, D52) oscillates
14–28 MHz signal.The detected audio signal from the FM­TV IC (IC1) is amplified at the buffer amplifier, and is then
applied to the mixer (Q41). The signal is mixed with oscillat­ed 14–28 MHz signal to produce the 13.25 MHz IF signal at
the mixer. The IF signal passes through the band switching
diode (RF unit; D72) and bandpass filter (RF unit; FI4). The
filtered signal is amplified at the 2nd IF amplifier (RF unit;
Q41), and is applied to the FM IF IC (RF unit; IC2, pin 16).

The detected signal is applied to the AF circuit (LOGIC unit)
for speaker, and applied to the A/V OUT jack (RF unit; J3)
via the RF amplifier (Q71).

4 - 7

FM-TV DETECTOR CIRCUITS (FM-TV UNIT)

AGC
amp.

VCO

PD

IF

amp.

DC

amp.

VIDEO

amp.

Loop
amp.

20

6

D2

D4

89

10

11 12 13 14

L1

R14

R15

R16

The detected signal

C16

L3L2

R13 R12

C16

R16

R15

R6

R8

1921222425

C18

R78

R77

R3 C4

CP1

FMTV5

BPF

IF

amp.

IC1

FI1

C3

R4

"IFIN" signal from the 1st mixer
circuit (RF unit; IC1, pin 6)

IC2 (FM-TV DETECTOR IC)

4 - 8

Pin Port

Description

number name

5

6

7

8

9

10

11

12

16

17

B1C

B2C

B3C

65MC

30MC

SHIFT

DBL1

DBL2

470MC

600MC

Outputs low-pass filter select signal.

Low : When frequencies 0.5 to 1.9

MHz are displayed.

Outputs bandpass filter select signal.

Low : When frequencies 1.9 to 15

MHz are displayed.

Outputs bandpass filter select signal.

Low : When frequencies 15 to 30

MHz are displayed.

Outputs bandpass filter select signal.

Low : When frequencies 65 to 108

MHz are displayed.

Outputs bandpass filter select signal.

Low : When frequencies 30 to 65

MHz are displayed.

Outputs control signal for the VCO shift
circuit (VCO unit; Q21, D61).

High : While the 1st VCO is shifting.

Outputs control signal for the doubler1
circuit (RF unit; Q26, D65, D67).

Outputs control signal for the doubler2
circuit (RF unit; Q26, D66, D68).

Outputs low-pass and bandpass filters
select signal.

Low : When frequencies 470 to 600

MHz are displayed.

Outputs low-pass and bandpass filters
select signal.

Low : When frequencies 600 to 750

MHz are displayed.

LINE

BATV

VCC

HV

+3V

3V

R3V

4.5V

5V

12V

15V

DESCRIPTION

The voltage from the attached battery.
The same voltage as the BATV line (battery volt-

age).
Common 3V converted from VCC line by the

+3V converter circuit (LOGIC unit; Q6, Q39)
using the “POWERC” signal from the CPU
(LOGIC unit; IC11, pin 28).

Common 3V converted from the VCC line by the
+3V regulator circuit (LOGIC unit; IC3).
The output voltage is applied to the RESET cir­cuit (LOGIC unit; IC5, pin 2).

Receive 3V controlled by the R3V regulator cir­cuit (LOGIC unit; Q4, Q5) using the +3SC signal
from the CPU (LOGIC unit; IC11, pin 27).

Common 4.5V converted from the VCC line by
the DC-DC converter (LOGIC unit; IC801).
The output voltage is applied to the TFT driver
(LOGIC unit; IC901) and the TFT back light dri­ver (LOGIC unit; Q821).

Common 5V converted from the VCC line by the
DC-DC converter (LOGIC unit; T1).
The output voltage is applied to the OSD IC
(LOGIC unit; IC902), etc.

Common 12V converted from VCC line by the
DC-DC converter (LOGIC unit; T1).
The output signal is applied to the TFT driver
(LOGIC unit; IC901).

Common 15V converted from the VCC line by
the DC-DC converter (LOGIC unit; T1).
The output signal is applied to the TFT LCD
(LOGIC unit; DS54).

4-4 POWER SUPPLY CIRCUITS

VOLTAGE LINE

4-5 PORT ALLOCATIONS

4-5-1 EXPANDER IC (RF UNIT; IC5)

4 - 9

Pin Port

Description

number name

42

45

51
52

54

56

57

58

59

60
61
62

63

64

ECS

PSTB

OSSTB

TGSTB

DATA

UHF3VC

174MC

108MC

HFC

ATT3
ATT2
ATT1

AM

WFM

Outputs chip select signal for the
EEPROM (LOGIC unit; IC2, pin 1).

I/O port for strobe signal from/to the
PLL IC (VCO unit; IC3, pin 3).

Outputs chip select signal for the color
LCD.

Outputs color LCD load signal.

• Outputs color LCD control signal.

• Outputs serial data for the LCD con­trollor.

Outputs bandpass filter select signal.

Low : When frequencies 330 to 470

MHz are displayed.

Outputs bandpass filter select signal.

Low : When frequencies 174 to 225

MHz are displayed.

Outputs bandpass filter select signal.

Low : When frequencies 108 to 174

MHz are displayed.

Outputs control signal for the HF band
receiver regurator circuit (RF unit; Q5).

Low : When frequencies 0.5 to 30

MHz are displayed.

Outputs attenuater control signal.

High : While attenuater is ON.

Outputs AM mode select signals.

Low : When AM is selected.

Outputs WFM mode select signals.

Low : When WFM is selected.

4-5-2 CPU (LOGIC UNIT; IC11)

Pin Port

Description

number name

2
9

10

11

15

17

18

19
20
21

23

24

25

26

27

29

30

31

32

33

41

THERMC

TRACC

FSET

TCON

VRC

CHGC

AMUTE

CLOUT

CLIN

BEEP

POWERC

AFON

RXC

DCDC_C

+3SC

CONVC

TVC

LIGHT

CPUHV

RESET

ECK

Input port for the receiver’s internal
temperature detection.

Outputs tracking control signal.
Outputs control signal for the RIT fre-

quency.
Outputs control signal for the CTCSS

regulator circuit (LOGIC unit; IC9, pin

3).
Low : While the CTCSS is ON.

Outputs level control signal for the AF
volume.

Outputs battery charger control signal.

High : While charging battery.

Outputs the AF mute switch (LOGIC
unit; Q37) control signal.

High : While squelched.

Outputs the cloning signal.
Input port for the cloning signal.
Outputs beep audio signals.
Outputs the +3V regurator control sig-

nals.

Low : Power switch is pushed.

Outputs control signal for the AF
amplifier regurator circuit.

High : Activates the AF amplifier cir-

cuit.

Outputs control signal for the receiver
regulator circuit.

Outputs the DC-DC converter (LOGIC
unit; IC801, pin 2) control signal.

Low : While color LCD is displayed.

Outputs the +3S regurator control sig­nal.

Outputs control signal for the convert­er circuit.

Low : When frequencies above

1150 MHz are displayed.

Outputs control signal for the TV
receive circuit.

Low : While TV band receiving.

Outputs key and LCD backlight con­trol signal.

High : Lights ON.

Input port for connecting the external
power supply detection.

Low : While connecting the external

power supply.
Input port for the RESET signal.
I/O port for the EEPROM (LOGIC unit;

IC2, pin 1) serial clock.

5 - 1

5-1 PREPARATION

‘‘

REQUIRED TEST EQUIPMENT

‘‘

ENTERING ADJUSTMENT MODE

q Turn power OFF.
w Input the square wave (as illustration at page 5-2) to the [SP] jack (RF unit; J2).
e Push and hold the [FUNC] key, and then turn power ON.

NOTE: When turning power OFF disconnecting the square wave, cancelled the adjustment mode.

‘‘

OPERATING ON THE ADJUSTMENT MODE

Change the adjustment item or channel : [Ω] or [≈]
Change the value : [DIAL]

‘‘

FM-TV FREQUENCY ADJUSTMENT ([OTH-2] ONLY)

When adjusting “FM-TV FREQUENCY”, need to remove the FM-TV unit from the IC-R3 as follow.

q Unsoldering 3 points A and 3 points B.
w Pull up the FM-TV unit.

EQUIPMENT

DC power supply

Digital multimeter

Oscilloscope

Audio generator

GRADE AND RANGE

Output voltage : 4.5 V DC
Current capacity : 1 A or more

Input impedance : 10 MΩ/DC or better
Frequency range : DC–20 MHz

Measuring range : 0.01–10 V
Frequency range : 1–3000 Hz

Measuring range : 0.01–10 V

EQUIPMENT

Frequency counter

Standard signal
generator (SSG)

Digital DC voltmeter

GRADE AND RANGE

Frequency range : 0.1–2500 MHz
Frequency accuracy: ±1 ppm or better
Sensitivity : 100 mV or better

Frequency range : 0.1–2500 MHz
Output level : 0.1 µV–32 mV

(–127 to –17 dBm)

Input impedance : 10 MΩ/DC or better

SECTION 5 ADJUSTMENT PROCEDURES

unsoldering here

unsoldering here

REMOVING FM-TV UNIT

A

B

5 - 2

Standard signal
generator

1/8" (3.5 mm)
3-conductor plug

GND

CLONE

Audio generator

1.5 V 3 V

10 Hz

When entering the adjustment mode,
input the square wave as below from
the audio generator

CONNECTION
DC POWER CABLE CONNECTION

Power supply

4.5 V / 1 A

5 - 3

5-2 PLL ADJUSTMENT

“TV RECEIVING SYSTEM”, “REFERENCE FREQUENCY” AND “DETECTOR OUTPUT VOLTAGE” adjustments must be per­formed at “ADJUSTMENT MODE”.

1ST VCO
LOCK
VOLTAGE
(SHIFT ON)

(SHIFT OFF)

2ND VCO
LOCK
VOLTAGE

CONVERTER
VCO LOCK
VOLTAGE

TV MODE
REFERENCE
FREQUENCY

TV
RECEIVING
SYSTEM

REFERENCE
FREQUENCY

DETECTOR
OUTPUT
VOLTAGE

ADJUSTMENT

ADJUSTMENT ADJUSTMENT CONDITION

MEASUREMENT

VALUE

POINT

UNIT LOCATION UNIT ADJUST

1

2

1

1

1

1

1

1

• Displayed frequency :

799.995 MHz

• Receiving

• Displayed frequency :

0.495 MHz

• Receiving

• Displayed frequency :

0.495 MHz

• Receiving

• Displayed frequency :

1150.000 MHz

• Receiving

• Displayed frequency :

97.45 MHz

• Mode :TV

• Connect an SSG to the antenna
connector and set as:

Level :

1 mV* (60 dBµ)

Modulation : OFF

• Receiving

• Displayed TV receiving system
adjustment menu (TV ch).

• Displayed frequency :

(FR ch) 1260.000 MHz

• Receiving

• Displayed frequency :

(TL ch) 30.100 MHz

• Connect an SSG to the antenna
connector and set as:

Level : 1 mV

* (60 dBµ)

Modulation : OFF

• Receiving

VCO

VCO

VCO

RF

DISPLAY

RF

RF

Connect the digital
multi-meter to the
check point CP1.

Connect the digital
multi-meter to the
check point CP2.

Connect the digital
multi-meter to the
check point CP3.

Connect the fre­quency counter to
the check point
CP6.

Connect the fre­quency counter to
the check point
CP5.

Connect the digital
multi-meter to the
check point CP1.

14.5 V

2.5 V

3.2 V – 5.2 V

0.8 V

2.5 V

4.5

1320.0000 MHz

1.0 V

VCO

VCO

VCO

RF

Top

panel

Top

panel

RF

L64

L63

Verify

L919

L902

[DIAL]

[DIAL]

L21

*This output level of the standard signal generator (SSG) is indicated as SSG’s open circuit.

5 - 4

1st VCO lock voltage (shift on)
adjustment

L64

1st VCO lock voltage (shift off)
adjustment

L63

TV mode reference frequency
check point

CP6

TV mode reference frequency
adjustment

L902

Detector output voltage
check point

CP1

Detector output voltage
adjustment

L21

1st VCO lock voltage
check point

CP1

2nd VCO lock voltage
check point

CP2

Converter VCO lock voltage
check point

CP3