Icom Ic-pw1 User manual

HF/50 MHz ALL BAND

LINEAR AMPLIFIER

iC-PW1

INTRODUCTION

This service manual describes the latest service information for

the IC-PW1 HF/50 MHz ALL BAND LINEAR AMPLIFIER at

the time of publication.

To upgrade quality, all electrical or mechanical parts and inter-

nal circuits are subject to change without notice or obligation.

DANGER

HIGH VOLTAGE! NEVER touch the antenna con-

nector or the power supply section in the linear amplifier

while connecting the IC-PW1 to an AC outlet.

NEVER carry the linear amplifier by yourself. At least two

persons must carry the linear amplifier since it weights ap-

prox. 25 kg (55.12 lb).

NEVER expose the IC-PW1 to rain or moisture since fire

or shock hazard could occur.

NEVER touch the IC-PW1 with metal strips, wire, etc.

These materials may cause fires and electric shocks.

ORDERING PARTS

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

1140003830 S.IC TC4W66F IC-PW1 MAIN UNIT 1 piece

8810003160 SET Screw 3 ×6 ZK IC-PW1 CHASSIS 6 pieces

Addresses are provided on the inside back cover for your

convenience.

REPAIR NOTES

1. Make sure a problem is internal before disassembling the

linear amplifier or the remote controller.

2. DO NOT open the linear amplifier or the remote controller

until the linear amplifier 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 insu-

lated tuning tool MUST be used for all adjustments.

5. DO NOT keep power ON for a long time when the linear

amplifier is defective.

6. READ the instructions of test equipment thoroughly

before connecting equipment to the linear amplifier.

MODEL VERSION SYMBOL

Europe

Europe-1

IC-PW1

USA

EUR

EUR-1

U.S.A.

TABLE OF CONTENTS

SECTION 1 SPECIFICATIONS

SECTION 2 INSIDE VIEWS

SECTION 3 CIRCUIT DESCRIPTION

3-1 LINEAR AMPLIFIER CIRCUITS......................................................................................... 3 - 1

3-2 ANTENNA TUNER CIRCUITS ........................................................................................... 3 - 2

3-3 PROTECTION CIRCUITS.................................................................................................. 3 - 3

3-4 POWER SUPPLY CIRCUITS ............................................................................................ 3 - 4

3-5 PORT ALLOCATIONS ....................................................................................................... 3 - 4

SECTION 4 ADJUSTMENT PROCEDURES

4-1 PREPARATION................................................................................................................... 4 - 1

4-2 PAAND FRONT UNITS ADJSTMENT ............................................................................... 4 - 2

4-3 MAIN UNIT ADJUSTMENT ................................................................................................ 4 - 3

SECTION 5 PARTS LIST

SECTION 6 MECHANICAL PARTS AND DISASSEMBLY

SECTION 7 SEMI-CONDUCTOR INFORMATION

SECTION 8 BOARD LAYOUTS

8-1 ANT-SW UNIT .................................................................................................................... 8 - 1

8-2 C-NET BOARD................................................................................................................... 8 - 1

8-3 L-NET BOARD.................................................................................................................... 8 - 2

8-4 H-NET BOARD................................................................................................................... 8 - 2

8-5 CONNECT BOARD ............................................................................................................ 8 - 3

8-6 COMBINR UNIT ................................................................................................................. 8 - 4

8-7 SPLITR UNIT...................................................................................................................... 8 - 5

8-8 PA UNIT.............................................................................................................................. 8 - 6

8-9 DET BOARD....................................................................................................................... 8 - 7

8-10 JACK-1 UNIT...................................................................................................................... 8 - 8

8-11 SW BOARD ........................................................................................................................ 8 - 9

8-12 FILTER UNIT..................................................................................................................... 8 - 11

8-13 MAIN UNIT ....................................................................................................................... 8 - 13

SECTION 9 BLOCK DIAGRAM

SECTION 10 VOLTAGE DIAGRAM

10-1 WIRING DIAGRAM........................................................................................................... 10 - 1

10-2 SPLITR, PA, AND COMBINR UNITS............................................................................... 10 - 2

10-3 FILTER UNIT .................................................................................................................... 10 - 3

10-4 PA UNIT............................................................................................................................ 10 - 4

10-5 FRONT UNIT.................................................................................................................... 10 - 5

10-6 MAIN UNIT ....................................................................................................................... 10 - 6

10-7 TUNER UNIT.................................................................................................................... 10 - 7

1 - 1

MGENERAL

• Frequency range : 1.800–1.999 MHz

3.500–3.999 MHz

4.630 MHz

7.000–7.300 MHz

10.100–10.150 MHz

14.000–14.350 MHz

18.068–18.168 MHz

21.000–21.450 MHz

24.890–24.990 MHz*1

28.000–29.700 MHz*1

50.000–54.000 MHz

*1The USA version can only be used the antenna tuner on the 24–28 MHz bands.

• Duty cycle : Full duty

• Input connector : SO-239 ×2 (50 Ω)

• Output connector : SO-239 ×4 (50 Ω)

• Power supply voltage : 90 V–132 V AC or 180 V–264 V AC

(single-phase; 50/60 Hz)

• Usable temperature range : –10 ˚C to +40 ˚C; +14 ˚F to +104 ˚F

• Dimensions : Linear amplifier 350(W)×265(H)×375(D) mm;

(Projections not included) 13.78(W)×10.43(H)×14.76(D) in

Remote controller 205(W)×71(H)×68.3(D) mm;

8.07(W)×2.80(H)×2.69(D) in

• Weight : 25 kg; 55.12 lb (Included in the remote controller)

(Included in the remote controller)

MLINEAR AMPLIFIER

• Output power :

*1EUR-1 version is 450–550 W;

*2EUR-1 version is 450–550 W PEP

• Driving power : Max. 100 W

• Sprious emissions : Less than –60 dB (for HF bands)

Less than –70 dB (for 50 MHz band)

MANTENNA TUNER

• Output matching range : 16.7–150.0 Ω*1(for HF bands)

20.0–125.0 Ω(for 50 MHz band)

*1Specifications of 1.9 MHz band guaranteed 1.85–1.95 MHz

• Auto tuning accuracy : VSWR 1.5:1 or less

• Min. required input power : 60 W

• Insertion loss : Less than 1 dB (after tuning)

SECTION 1 SPECIFICATIONS

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

MODE

CW, RTTY

SSB

INPUT AC VOLTAGE

90–132 V AC

450–600 W*1

450–600 W PEP*2

180–264 V AC

950–1150 W

950–1150 W PEP

2 - 1

SECTION 2 INSIDE VIEWS

ANT-SW UNIT

SW BOARD

JACK1 UNIT

COMBINR UNIT

FRONT

SIDE

SPLITR UNIT

PA-1 UNIT

PA-2 BOARD

PA-3 BOARD

PA-4 BOARD

FILTER UNIT

FRONT UNIT

POWER UNIT

LOWPASS FILTER

2 - 2

TUNER UNIT

CONNECT BOARD

FRONT

SIDE

MAIN UNIT

C-NET BOARD

H-NET BOARD

L-NET BOARD

DET BOARD

3-1 LINEAR AMPLIFIER CIRCUITS

3-1-1 EXCITER INPUT SWITCHING CIRCUIT

(SPLITR UNIT)

The applied signal from the exciter (transceiver) is passed

through the exciter select circuit (RL1) then applied to the

THROUGH/AMP switching relay (RL2). The switched signal

is passed through the attenuator circuit (R3–R6) when the

amplifier is activated. The attenuated signal is applied to the

power split circuit (L2–L4, L6, R9–R12).

When “THROUGH” is selected, the signal from the exciter

select circuit is applied to the FILTER unit via J8.

The attenuator circuit attenuates the switched signal approx.

1 dB to protect the amplifier circuits from excessive input

power and stabilizes the amplifying operation.

3-1-2 POWER SPLITTER CIRCUIT (SPLITR UNIT)

The power splitter circuit converts the antenna impedance to

1⁄4(12.5 Ω) at L2, then the applied RF power level is divid-

ed at the hybrid circuit (L3, R9, R10). The divided RF signals

are separately passed through another hybrid circuit (L4,

R11 and L6, R12) to convert the impedance to 50 Ωand

divide the power level.

The power level divided signal is applied to the one of four

PA units (PA1–PA4) via J4 to J7.

The RF power level at J4, J5, J6 and J7 is approx. 1⁄5of

applied power (from the exciter).

3-1-3 POWER AMPLIFIER CIRCUITS

(PA1–4 BOARDS)

The power level divided signal from the SPLITR unit is

amplified at the power amplifier circuit (Q1a/b). The ampli-

fied signal is applied to the COMBINR unit.

Two power MOS-FETs (MRF150) and a negative feedback

circuit are employed for each PA unit to obtain a stable 300

W or higher of RF power and to maintain response gain for

all bands within 3 dB.

3-1-4 POWER COMBINER CIRCUIT

(CONBINR UNIT)

The amplified signals from the PA1 and PA2 boards are

combined at the hybrid circuit (L1, R1) to obtain a 500 W RF

level and the impedance is converted to 25 Ω.

The amplified signals from the PA3 and PA4 boards are

combined at another hybrid circuit (L2, R2).

Both signals are again combined at another hybrid circuit

(L3, R3) to obtain a 1 kW RF level and the impedance is

converted to 12.5 Ω. The combined signal is applied to the

FILTER unit via the impedance convertor (L5) for conversion

to 50 Ωimpedance.

3-1-5 FILTER CIRCUIT (FILTER UNIT)

The signal from the CONBINR unit is passed through one of

8 low-pass filters.

The filtered signal is applied to the matching circuit.

SECTION 3 CIRCUIT DESCRIPTION

C26

"HV" to PA1 board

via the J11, pin 1

"T8V" to PA1 board

via the J11, pin 5 and 6

GND

TEMP

DRIV

J2 RL1

C18

C19

L1 L8

D2 R7

R2 C5

R17

C21 R16 R18

C22 IC1 L11

R14 R15

R13 C9 C10

D4 C8

C17

R9 R10

C11 L4

R11

J4 PA1

J5 PA2

PA3

PA4

R12

C14

IN1

IN2

TRU

• SPLITTER CIRCUIT

RL2

3 - 1

3 - 2

2-step (3-step for the 50 MHz band) Chebyschev low-pass

filters are adopted, to obtain –60 dB or less higher harmon-

ic emissions for all HF bands or –70 dB or less for the 50

MHz band.

The filtered signal is passed through or bypasses the anten-

na tuner and is then applied to one of four antenna connec-

tors via the antenna select relay (RL1–RL4) on the ANT-SW

unit.

3-2 ANTENNA TUNER CIRCUITS

3-2-1 MATCHING CIRCUIT (TUNER UNIT)

The matching circuit is a T-network. Using 2 tuning motors,

the matching circuit obtains rapid overall tuning speed.

Using relays (TUNER unit; RL1–RL10, L-NET board; RL1,

RL2, H-NET board; RL1–RL10), the relay control signals

from the antenna tuner CPU (MAIN unit; IC12) via the relay

driver (MAIN unit; IC14) ground one of the taps of L3–L5 (L-

NET board) or L11–L15 (H-NET board) and add network

capacitors (C-NET board). After selecting the coils and

capacitors, 2 motors (TUNER unit; MF1, MF2) adjust C1

and C2 using the antenna tuner CPU and the motor driver

(MAIN unit; IC15) to obtain a low SWR (Standing Wave

Ratio).

3-2-2 DETECTOR CIRCUIT

(MAIN AND FILTER UNITS)

(1) SWR detector

Forward and reflected power are picked up by a current

transformer (FILTER unit; L22), detected by D15 and D16,

and then applied to the MAIN unit.

The applied signals are amplified at the SWR amplifier

(MAIN unit; IC31a/b). The amplified voltages are applied to

the antenna tuner CPU (MAIN unit; IC12, pins 2, 3). The

CPU detects the SWR.

(2) Reactance components detector

Reactance components are picked up by comparing the

phase of the RF current and RF voltage. The RF current is

detected by L3 and R4 (DET board), and then amplified at

IC1a and IC2d. The amplified RF current is applied to the

phase comparator (DET board; IC4, pin 13). The RF volt-

ages are detected at C1–C3 on the DET board, and ampli-

fied at IC1c and IC2a, then applied to the phase comparator

(IC4, pin 1). The output signal from the phase comparator

(IC4, pin 6 for RF voltage, pin 9 for RF current) is rectified at

D13 and D14 for conversion into DC voltage. The rectified

voltage signals are combined, then applied to the antenna

CPU (MAIN unit; IC12, pin 64) after being amplified at IC9a

on the MAIN unit.

ECL-IC is used for IC1 and IC2 on the DET board to ensure

quick and stable signal detection even at low RF signal level

input.

(3) Resistance components detector

Resistance components are picked up by L5, R14 and R21,

and detected by Q1, D11 and D12 on the DET board. The

detected resistance components are amplified at IC9a on

the MAIN unit, and then applied to the antenna CPU (IC12,

pin 1).

3-2-3 MOTOR CONTROL CIRCUIT

(MAIN UNIT AND C-NET, L-NET, H-NET

BOARDS)

The control circuit of the internal antenna tuner consists of

the CPU, EEPROM, tuning motors and tuning relays.

(1) CPU and EEPROM (MAIN unit)

The antenna tuner CPU (IC12) controls the tuning motors

via the motor driver (IC15) and tuning relays via the relay dri-

ver (IC14, Q9–Q14). The CPU memorizes the best preset

position and the contents are stored in the EEPROM (IC7)

without the need for a backup battery.

• DETECTOR CIRCUIT

COUPLER COUPLER

L3, R4 L5, R14, R21

Impedance

detector Phase

detector

Q1, D11,

D12 D3, D4,

D5, D6,

D13, D14,

IC2, IC4

IC9

Tuner CPU

IC12

From FILTER unit To C-NET board

DET board

MAIN unit

Amplifier

3 - 3

(2) Tuning controls (MAIN unit)

A motor driver (IC15) rotates the tuning motors (MF1, MF2)

to obtain a low SWR.

(3) Tuning relays (C-NET, L-NET and H-NET boards)

According to the operating frequency band and antenna

condition, tuning relays select the capacitors and coils.

3-3 PROTECTION CIRCUITS

3-3-1 GENERAL

The IC-PW1 has two protection systems. One system

bypasses the power amplifier, and the other system shuts

down the internal power supply activation.

Protection activates when:

• a mismatched frequency band signal is transmitted.

• the ALC control level exceeds the control range.

• the power level balance between the 4 PA units becomes

unbalanced.

• the output voltage of the internal power supply (VD)

exceeds 55 V DC.

• the current of the power amplifiers (ID) exceeds 50 A.

• the heatsink temperature of the power amplifier exceeds

+100˚C (212˚F).

• the applied AC voltage exceeds the specified value.

The main CPU controls the THROUGH/AMP switch and

internal power supply operation.

3-3-2 ALC CIRCUIT (MAIN UNIT)

The ALC (Automatic Level Control) circuit automatically lim-

its RF output power by controlling the input level of the

exciter.

(1) FOR-ALC

The detected “FOR” voltage signal from the SWR detector

circuit (FILTER unit; D15, D16, L22) is op-amplified at IC1a

then applied to the ACC2 socket (JACK1 unit; J5, pin 5) via

the ALC adjustment pot (JACK1 unit; R1) and ALC2 jack

(JACK2 unit; J7).

(2) ID-ALC

In the IC-PW1, internal power supply voltage (ID) is used for

ID-ALC. The power supply voltage (ID) is amplified at the op-

amplifier (IC1c), then applied to the ACC2 socket.

(3) SWR-ALC

SWR-ALC protects the power amplifiers (PA1–PA4 boards;

Q1a/b) when SWR worsens and when dielectric break-

down/discharge from excessive voltage rises.

The detected “REF” voltage signal from the SWR detector

circuit (FILTER unit; D15, D16, L22) is op-amplified at the

SWR/DRIVE amplifier (IC1b) then applied to the ACC2

socket (JACK1 unit; J5, pin 5).

(4) DRV-ALC

DRV-ALC activates when the exciter input exceeds 120 W

to protect the power amplifiers. The op-amplified “REF” sig-

nal at the SWR/DRIVE amplifier (IC1b) is used for operation.

However, the limiter circuit on the SPRITR unit (D4, D5) is

activated for momentary excessive input such as leading

edge power, etc.

3-3-3 DRIVING POWER DETECTOR CIRCUIT

(SPLITR AND MAIN UNITS)

Aportion of the attenuated input power from the exciter input

switching circuit (SPLITR unit; RL1) is divided by R7 and R8,

and then rectified at D3, R2 and C5 for conversion to DC

voltages. The rectified DC voltages are applied to the drive

amplifier (MAIN unit; IC21a/b). The amplified DC voltages

are applied to the main CPU (MAIN unit; IC26)

• ALC CIRCUITS

From SPLITR unit RL5

From TUNER unit

"T13" from MAIN unit

VSWR detector

D15, D16, L22

RF power control

IC1

ACC socket1,

pin 5

ALC selector ALC1

ALC2

Relay driver

IC18

ACC socket2,

pin 5

Main CPU IC26

RL1

ALC amp.

Id controlRegurator

IC1

FOR

SWR/DRIVE

control

IC1

REF

To DET board

FILTER UNIT

3 - 4

3-3-4 TEMPERATURE DETECTOR CIRCUIT

(SPLITR AND MAIN UNITS)

The temperature detector circuit detects the temperature of

the heatsink for final FETs and controls amplifying operation.

A thermistor (SPLITR unit; R16) detects temperature of the

heatsink for final FETs, and the detected temperature signal

(DC voltage) is applied to the main CPU (MAIN unit; IC26,

pin 12), to control the cooling fans and amplifying operation.

Common 5 V is applied to the thermistor for reference.

3-3-5 DRIVING FREQUENCY DETECTOR CIRCUIT

(SPLITR AND MAIN UNITS)

A portion of the RF signal from RL1 (SPLITR unit) is divided

at C18 and C19, then applied to the driving frequency detec-

tor circuit in the MAIN unit as the “F” signal.

The “F” signal from the SPLITR unit is amplified at the lim-

iter amplifier (MAIN unit; IC30) after being amplified at Q34

and Q35. The amplified signal is divided at the divider (MAIN

unit; IC20) for conversion to pulse-type signals. The signals

are applied to the main CPU (MAIN unit; IC26, pin 76). The

CPU counts the number of pulses as the driving frequency,

then controls the protector for frequency band selection.

The driving frequency detector circuit detects the input

power level at the same time to prevent malfunction at low

power level inputs.

LINE

H12

12 V

5 V

+5 V

–5 V

–13 V

T13

T8V

DESCRIPTION

+12 V line from the regulator circuit. The output

voltage is applied to the meter lamp (FRONT

unit; DS1, DS2).

12 V controlled from a H12 line by the relay con-

trol circuit (IC8, IC9).

5 V DC converted from a 12 V line at IC5 on the

MAIN unit. The voltage is used for the phase

detector on the DET unit.

5 V DC converted from a S12 line (+12 V) at IC6

on the FRONT unit. The voltage is used for the

output expander IC on the FRONT unit.

–5 V DC converted from a –13 V line at IC5 on

the DET board.

–13 V DC converted from a H12 (+12 V) line at

IC8 on the MAIN unit.

Transmit 13 V DC converted from a H12 (+12 V)

line at Q3 on the MAIN unit.

Transmit 8 V DC converted from a T13 line at

IC1 on the SPLITR unit. The output voltage is

used for PA1, PA2, PA3 and PA4 on the PA unit.

45 V line from the regulator circuit. The voltage is

used for PA1, PA2, PA3 and PA4 on the PA unit.

3-4 POWER SUPPLY CIRCUITS

• VOLTAGE LINE

Pin Port Description

number name

3-5 PORT ALLOCATIONS

3-5-1 EXPANDER IC (SWITCH BOARD; IC1)

I1L

I2L

A4L

A3L

A2L

A1L

Outputs INPUT “1” LED control signal.

High:While INPUT “1” LED is ON.

Outputs INPUT “2” LED control signal.

High:While INPUT “2” LED is ON.

Outputs ANT “4” LED control signal.

High:While ANT “4” LED is ON.

Outputs ANT “3” LED control signal.

High:While ANT “3” LED is ON.

Outputs ANT “2” LED control signal.

High:While ANT “2” LED is ON.

Outputs ANT “1” LED control signal

High:While ANT “1” LED is ON.

Pin Port Description

number name

3-5-2 EXPANDER IC (SWITCH BOARD; IC2)

VML

SML

AML

TML

IML

PML

Outputs “VD” LED control signal.

High:While “VD” LED is ON.

Outputs “SWR” LED control signal.

High:While “SWR” LED is ON.

Outputs “ALC” LED control signal.

High:While “ALC” LED is ON.

Outputs “TEMP” LED control signal.

High:While “TEMP” LED is ON.

Outputs “ID” LED control signal.

High:While “ID” LED is ON.

Outputs “PO” LED control signal.

High:While “PO” LED is ON.

3 - 5

Pin Port Description

number name

Outputs “3.5” LED control signal.

High:While “3.5” LED is ON.

Outputs “1.8” LED control signal.

High:While “1.8” LED is ON.

Outputs “AMP/PROTECT” LED con-

trol signal.

High:While “AMP/PROTECT” LED is

ON.

Outputs “AMP/PROTECT” LED con-

trol signal.

High:While “AMP/PROTECT” LED is

ON.

Outputs “TUNER” LED control signal.

High:While “TUNER” LED is ON.

Outputs “TRANSMIT” LED control sig-

nal.

High:While “TRANSMIT” LED is ON.

Outputs “AUTO” LED control signal.

High:While “AUTO” LED is ON.

3_5M

1_9M

PROL

PAL

TUNL

TRANS

AUTOL

3-5-4 EXPANDER IC (SWITCH BOARD; IC4)

Pin Port Description

number name

3-5-3 EXPANDER IC (SWITCH BOARD; IC3)

50ML

24ML

7ML

10ML

14ML

18ML

Outputs “50” LED control signal.

High:While “50” LED is ON.

Outputs “24” LED control signal.

High:While “24” LED is ON.

Outputs “7” LED control signal.

High:While “7” LED is ON.

Outputs “10” LED control signal.

High:While “10” LED is ON.

Outputs “14” LED control signal.

High:While “14” LED is ON.

Outputs “18” LED control signal.

Pin Port Description

number name

3-5-5 SHIFT REGISTER IC (SWITCH BOARD; IC7)

ANT

TUNER

MET1

MET2

BUP

BDN

I1/2

Input port for the antenna switching

signal.

Low: When “ANT” switch is pushed.

Input port for the tuner power ON/OFF

switching signal.

Low: When “TUNER” switch is

pushed.

Input port for the PA power ON/OFF

switching signal.

Low: When “AMP/PROTECT” switch

is pushed.

Input port for the meter mode select

signal for meter-1.

Low: When “METER-1” switch is

pushed.

Input port for the meter mode select

signal for meter-2.

Low: When “METER-2” switch is

pushed.

Input port for the band up signal.

Low: When “UP” switch is pushed.

Input port for the band down signal.

Low: When “DOWN” switch is

pushed.

Input port for the port select signal.

Low: When “INPUT” switch is select-

ed.

3 - 6

Pin Port Description

number name Pin Port Description

number name

3-5-6 CPU (MAIN UNIT; IC26)

FOR

REF

ALCM

TEMP

USA

JPN

SEND

I1/2

1.9MF

3.5MF

7MF

10MF

14MF

18MF

24MF

50MF

Input port for the forward power volt-

age from IC2 (pin 1).

Input port for the reflected voltage

from IC2 (pin 7).

Input port for the voltage from power

supply “VO” signal. The voltage is

controlled by R197.

Input port for the current from power

supply “IO” signal. The current is con-

trolled by R22.

Input port for the ALC signal which is

used for the METER-2.

Input port for the signal about temper-

ature of the heatsink.

Input port for the version set signal.

Low: USA version is set.

Input port for the version set signal.

Low: JPN version is set.

Input port for the transmit switching

signal.

Low: While transmitting

Outputs a input port select signal.

Low: When INPUT1 is selected.

High:When INPUT2 is selected.