Sea 235 User manual

SEA 235 OPERATOR’S MANUAL

Digital Single Sideband Radiotelephone

TABLE OF CONTENTS

GENERAL OPERATIONS...............................................................................1

TECHNICAL SPECIFICATIONS...................................................................1

GENERAL INFORMATION...........................................................................2

UNDERSTANDING CHANNEL MEMORY .................................................3

LCD DISPLAY CHARACTERS.....................................................................4

FRONT PANEL CONTROLS.........................................................................4

BASIC OPERATION.......................................................................................5

TURNING THE RADIO ON...........................................................................6

OPERATING THE TRANSMITTER..............................................................6

THE TUNED INDICATOR.............................................................................6

DEMAND TUNE.............................................................................................7

NOISE BLANKER OPERATION...................................................................7

SELECTING A VOICE CHANNEL................................................................8

SELECTING A TELEX CHANNEL...............................................................8

SELECTING A CHANNEL BY BIN NUMBER............................................9

CHANGING THE DISPLAY VIEW...............................................................9

ENTERING A RECEIVE ONLY FREQUENCY..........................................10

SELECTING THE EMERGENCY CHANNEL............................................10

SENDING THE DISTRESS ALARM SIGNAL............................................11

OVERRIDE....................................................................................................12

SQUELCH OPERATION..............................................................................12

CLARIFIER OPERATIONS..........................................................................12

OPERATING THE MEMORY BROWSE....................................................13

ADVANCED OPERATIONS..........................................................................14

SELECTING THE PROGRAM MENU........................................................14

STORING THE DISPLAYED FREQUENCY..............................................17

PROGRAMMING A NEW FREQUENCY...................................................19

ERASING A CHANNEL...............................................................................22

CHANGING THE NAME TAG OF A BIN...................................................23

SCANNING A CHANNEL GROUP .............................................................24

DIRECT FREQUENCY.................................................................................25

INTERCOM...................................................................................................26

FUNCTION MENUS .......................................................................................27

FUNCTION MENU OVERVIEW.................................................................27

FINDING A BIN WITH THE ALPHA MENU.............................................28

CHANGING THE MODE WITH THE MODE MENU................................29

SELECTING THE TRANSMIT POWER LEVEL........................................31

CHANGING THE DISPLAY ILLUMINATION ..........................................33

CHANGING THE SQUELCH THRESHOLD..............................................35

TABLE OF CONTENTS

SETUP MENU OPTIONS.............................................................................36

CHANGING THE KEY BEEP SETTING ....................................................39

CHANGING THE TUNER STATUS............................................................40

CHANGING THE CONTROLLER UNIT NUMBER ..................................41

CHANGING THE SSB AUDIO INPUT SOURCE.......................................41

CHANGING THE TELEX AUDIO INPUT SOURCE .................................43

CHANGING THE SSB AGC CHARACTERISTICS....................................44

CHANGING THE TELEX AGC CHARACTERISTICS..............................45

CHANGING THE VOGAD CHARACTERISTICS......................................46

AMATEUR OPERATING SYSTEM.............................................................47

THE RADIO AMATEUR OPERATING SYSTEM......................................47

FREQUENCY LISTINGS...............................................................................49

SEA 235 VOICE FREQUENCY LISTING...................................................49

DSC EMERGENCY CALLING FREQUENCIES ........................................60

SEA 235 TELEX FREQUENCY LISTING...................................................61

COAST STATIONS PROVIDING TELEX SERVICE.................................84

SEA SCRATCH PAD MEMORY LISTING.................................................85

SEA SCRATCH PAD WORKSHEET...........................................................91

SSB PROPAGATION TABLES....................................................................93

REAR PANEL..................................................................................................95

REAR PANEL CONNECTIONS...................................................................95

GLOSSARY......................................................................................................97

LIST OF FIGURES

Key Chart 1 - PROGRAM MENU 1...................................................................15

Key Chart 2 - PROGRAM MENU 2...................................................................16

Key Chart 3 - MODE MENU .............................................................................30

Key Chart 4 - POWER MENU ...........................................................................32

Key Chart 5 - DIMMER MENU.........................................................................34

Key Chart 6 - SETUP MENU 1..........................................................................37

Key Chart 7 - SETUP MENU 2..........................................................................38

GENERAL OPERATIONS

TECHNICAL SPECIFICATIONS

DIMENSIONS:

3.9” H x 10.5” W x 10.9” D

99mm H x 265mm W x 278mm D

WEIGHT:

10 Lbs.

4.5 Kgs.

ELECTRICAL:

Type Acceptance FCC Parts 80, 87, 90

FCC Identifier BZ6SEA235

Frequency Range (TX) 1.605 - 29.999 MHz

(RX) 0.490 - 29.999 MHz

Operating Temperature -30 degrees to +60 degrees C

Frequency Stability ±10 Hz

Operating Modes J3E, R3E, H3E (2182 KHz)

A1A (CW), F2B (TELEX)

Primary Voltage 13.6 V DC ± 15% (11.6 - 15.6 V DC)

Negative Rail Common to Chassis

Current Drain Receive Standby 1 Amp

Receive Full Audio 1.5 Amps

Transmit Voice 11 Amps

Transmit Two-Tone 17 Amps

Transmit TELEX 22 Amps

Output Impedance 50 ohms

Transmitter Output Power R3E, J3E 150 Watts PEP

F2B 150 Watts

LOW 50 - 75 Watts

VLOW 25 - 40 Watts

Receiver Sensitivity ≤1 µV for 12 dB SINAD

Audio Output 4 W @ ≤10% distortion into external

4 ohm load.

GENERAL OPERATIONS

GENERAL INFORMATION

CAUTION !

Do not attempt to transmit until the radiotelephone has warmed up for at least 3

minutes. Transmitting before the 3 minute warm up period can cause a violation

of the Federal Communications Commission regulations.

PROPAGATION

Medium Frequencies (MF) in the range of 300 KHz to 3 MHz propagate far

beyond the horizon. MF frequencies are generally usable within 300 miles

depending on the time of day, atmospheric conditions and man-made noise

levels.

High Frequencies (HF) in the range of 3 MHz to 30 MHz allow communications

over thousands of miles, again subject to the time of day and atmospheric

conditions. Interference tends to be more of a problem than on Very High

Frequencies (VHF) in the range of 30 MHz to 300 MHz.

To further understand MF/HF propagation, SEA’s “Mariners Guide to Single

Sideband” (MAN-0001-001) is highly recommended reading.

INSTALLATION (RF grounding & DC connections)

A radio frequency (RF) ground with a minimum of 100 sq. ft. is required for

proper operation. This ground system is not unique to SEA equipment. All

marine MF/HF radios have the same installation requirements for maximum

efficiency. Every connection to the ground should be made with a minimum of

2” wide copper strap. Proper wire size must be used between the radio and

power supply to prevent the DC (direct current) voltage at the radio from

dropping below 11.5 volts during transmit conditions. Should this occur, the

radio will drop to low power during transmit to prevent distorted transmissions.

It is recommended that an authorized SEA dealer perform the installation of your

MF/HF equipment to assure proper operation. For complete installation

instructions, refer to the “SEA 235 Installation Manual” (OPR-235-INST)

supplied with the radio.

RADIO PROTECTION

The SEA 235 monitors radio conditions such as DC supply voltage, internal

temperature and antenna VSWR. When these conditions are outside the preset

limits, the radio will revert to low power (approximately 75 Watts). The

display’s LOW indicator will light to indicate this condition. If this should occur

during an EMERGENCY situation, pressing will

override the monitoring sensors and allow FULL output power. The radio will

stay in the EMERGENCY OVERRIDE condition until the radio power is re-

cycled.

6FNC

GENERAL OPERATIONS

UNDERSTANDING CHANNEL MEMORY

CHANNELS

Nearly 1000 frequency pairs are stored as permanent channels in the SEA 235.

These channels are recalled by their assigned ITU or SEA channel number. ITU

numbers are known internationally and include all duplex frequency pairs

starting at 4 MHz and ending with 25 MHz. SEA numbers are assigned to those

frequencies that do not have an assigned ITU number. Currently all 2 to 3 MHz

frequencies and all simplex frequencies are assigned SEA channel numbers.

It is important to note that not all radios use the same channel numbers for

simplex or 2 to 3 MHz frequencies. Some radios use an “A”, “B”, “C” channel

assignment for frequencies not assigned an ITU channel number. For example,

if you refer to the SEA simplex channel 451 during communications, the person

you are communicating with may not have a channel 451. Their radio may have

the same frequency (4146.0 KHz) assigned to channel “4A”. For reliable

communications, always refer to the frequency when referencing simplex

channels or frequencies below 4 MHz.

BINS

In addition to the permanent memory, 200 user programmable channels known

as bins have been assigned for “scratchpad” memory. Approximately 170 of

these 200 channels have been programmed by SEA but may be changed at any

time. Bins may be programmed with any frequency, mode of transmission and

given a name tag besides a bin number.

SCAN CELLS

Consecutive bin numbers that have the same first three characters in their name

tag, are known as “scan cells”. SEA has programmed 170 of the 200 possible

bins into 23 different scan cells. Scan cells may be as short as one bin or as long

as 200 bins but should be kept to a reasonable length for scanning efficiency.

Each scan cell is organized with frequency pairs that are related to one another.

For example, bins 13 through 30 have been programmed with frequencies

assigned to the coast station KMI. Since the name tag’s first three characters are

“KMI”, and the bins are consecutively numbered, the bins may be scanned as a

group. If the bins do not have the same first three characters, the scan cell will

be split into two different cells. For instance, if bin 20 is renamed to “SEA 1”,

the KMI scan cell will be split into two cells. One cell will contain bins 13

through 19, while the other cell will contain bins 21 through 30. Bin 20 will be a

single channel scan cell called “SEA”. Scanning “KMI” could be done by

scanning bins 13 through 19 OR bins 21 through 30 but not both at the same

time.

Care should be given that a scan cell is not split unintentionally. Bins that will

not be scanned can be given any descriptive name tag.

GENERAL OPERATIONS

LCD DISPLAY CHARACTERS

Alphanumeric digits display channel numbers, frequencies and menus.

The NOISE BLANKER is activated.

The radio is in TRANSMIT.

The attached coupler has finished the tune process.

Indicates ½output power during transmit when on steady or

¼output power when flashing.

The radio will transmit a reduced carrier (H3E) of approximately 40W.

This mode is only available on the emergency frequency 2182.0 KHz.

Both transmit and receive will use LOWER SIDEBAND mode.

TELEX (J2B) mode will be used for transmit and receive.

The receiver SQUELCH is activated.

Relative output power when transmitting and audio signal strength

during receive. No bars indicates weak signal.

FRONT PANEL CONTROLS

Toggles power on/off.

Used to enter channel/frequency information and menu selections.

used alone, recalls emergency frequency 2182.0 KHz.

Toggles alarm generator test on/off.

Enables receiver noise blanker. When used with ,

transmits alarm signal.

Toggles squelch on/off.

Toggles display to show channel / bin #, frequency, or alpha name.

Accesses function menus and other function commands.

Selects displayed funtion menu or completes keyed entry.

Increases receiver frequency and scrolls selected function options.

Decreases receiver frequency and scrolls selected function options.

ENT

TND

LOW

AME

LSB

TLX

SQL

0 – 9

PWR

ALRM

SEND

SQL

FNC

ALRM

2182

GENERAL OPERATIONS

BASIC OPERATION

To turn the radio on, press

Wait 3 minutes for the synthesizer frequency

to stabilize before transmitting.

Rotate the volume control clockwise to

increase the volume level.

Press to activate the squelch.

Enter the desired channel number in three or

four digit form, followed by the key.

e.g.

The display will show the channel number for 2 seconds then change to display

the receive frequency.

Your SEA 235 is now set to transmit and receive on the selected channel.

For instructions on enabling other radio functions, see the table of contents for

the page number corresponding to the specific function.

Illustrations in this manual reflect the use of an attached SEA 1635 tuner. Differences in

tuner choice or radio programming may produce varying displays.

LOW SQL

TND

LOW SQL

451ENT

ENT

SQL

PWR

SEND SQL CH

PWR ALRM

FNC

2182

ENT

TX TND

LOW AME

LSB TLX

SQL

SEA 235 HF/SSB DIGITAL

RADIOTELEPHONE

GENERAL OPERATIONS

TURNING THE RADIO ON

Press

All display segments will be shown for a short

period followed by the radio model number,

then the controller (CT) and transceiver (RT)

software versions. The radio will then be set to

the MARINE mode on international emergency

frequency 2182.0 KHz using USB, J3E mode.

Wait 3 minutes for the synthesizer frequency to

stabilize before transmitting.

OPERATING THE TRANSMITTER

Keying the microphone push-to-talk button will switch the transmitter circuits

on, indicated by the “TX” indicator appearing

on the display. Speak in a normal voice with

your lips about one eighth of an inch away

from the microphone. Do not shout. Shouting

reduces intelligibility. The number of bars

displayed will change as the operator talks.

THE TUNED INDICATOR

The display’s “TND” indicator shows that the

SEA 1612 series, SEA 1635 or SEA 1631

antenna tuner has successfully matched the

antenna to the radio for maximum radiated

power. When the radio tuner mode is enabled,

entering a frequency or channel will cause the

“TND” indicator to extinguish and the “LOW”

indicator to appear. Speaking into the

microphone when the PTT is pushed will allow

the tuner to find a match. The “TND” indicator

will be displayed and the “LOW” indicator will

extinguish allowing full output power.

NOTE: If a frequency or channel has never been used, the “match” will take slightly

longer.

TX LOW

PWR

TX TND

LOW AME

LSB TLX

SQL

TX LOW

TX TND

LOW

GENERAL OPERATIONS

DEMAND TUNE

When the tuner senses a high VSWR, it will attempt to match the antenna

automatically during transmit. The Demand Tune function signals the tuner to

undergo a complete tune cycle even with an acceptable VSWR. This may be

needed on those rare occasions when the “TND” indicator does not appear or

when the operator suspects the match could be better. For the Demand Tune

function to operate, the SEA 1612C or SEA 1635 tuner must have the ‘DTN’

terminal connected to the SEA 235’s rear panel accessory connector P3 pin 10

(DMD TUNE). The ‘TUNER’ option in the radio’s “SETUP” menu must also

be programmed to “TNR ON”. Better tunes may occur using Demand Tune.

To Demand Tune, key the radio by holding the

PTT button on the microphone down, then

press and release to start the tune

cycle.

The “TND” indicator will turn off, the “LOW”

indicator will turn on and the radio will show

“TUNING”.

When the tuner has successfully completed the

match, the “LOW” indicator will disappear as

the “TND” indicator appears and the display

will show the VSWR. Release the microphone

PTT.

In the event that the tuner can not find a match

in 15 seconds, the radio will stop transmitting

and the display will read “NO TUNE”.

When tuning with voice, “HI VSWR” will

occasionally be displayed until the tune cycle

has successfully completed the antenna match.

NOISE BLANKER OPERATION

Use the key to toggle the noise

blanker on / off. The “NB” indicator shows the

noise blanker is on. The noise blanker will

help reduce impulse noise that may be caused

by on board equipment such as a bilge pump or

refrigerator compressor.

TX LOW

TX TND

NB TND

FNC

SEND

GENERAL OPERATIONS

SELECTING A VOICE CHANNEL

Enter the desired three or four digit ITU/SEA

channel number followed by

e.g.

The display will show the channel entered

followed by the receive frequency for the

selected channel.

Press to switch between the

channel number display and the frequency

display.

When the microphone PTT button is pressed,

the transmit frequency will be displayed when

in frequency display mode.

If the channel does not exist, “NO FREQ” is

displayed.

SELECTING A TELEX CHANNEL

The SEA 235 is capable of telex operations

when used with an appropriate modem.

Enter the desired three or four digit ITU/SEA

telex channel number followed by

e.g.

The display will show the channel entered

followed by the receive frequency for the

selected channel.

Press to switch between the

channel number display and the frequency

display.

When the microphone PTT button is pressed,

the transmit frequency will be displayed when

in frequency display mode.

If the channel does not exist, “NO FREQ” is displayed.

LOW

LOW TLX

LOW

ENT

2182 3ENT

2182 3

GENERAL OPERATIONS

SELECTING A CHANNEL BY BIN NUMBER

Enter the desired one, two or three digit bin

number followed by

e.g.

The display will show “BIN 24” for 1 second

followed by the name tag of the bin selected.

Press to cycle between the channel

display, frequency display, and alphanumeric

name tag displays.

When the microphone Push To Talk button is

pressed, the transmit frequency will be

displayed when in frequency display mode.

If the bin is not programmed, “NO FREQ” is

displayed.

CHANGING THE DISPLAY VIEW

is used to change the display view

between the alphanumeric name tag, channel

number and the associated frequency for that

channel.

For Bins, the key will change the

display view between the Alphanumeric name

tag, frequency and bin number.

When is pressed while on 2182.0 KHz,

the display will briefly show “EMER 0”.

To display the transmit frequency, press

to have the display show the receive frequency.

Press the microphone PTT to have the

transmitter frequency displayed.

LOW

ENT

2 4 ENT

TND

ALPHANUMERIC NAME TAG

TND

FREQUENCY VIEW

TND

BIN / CHANNEL VIEW

GENERAL OPERATIONS

UP DN

ENTERING A RECEIVE ONLY FREQUENCY

Enter any frequency using four, five, or six

digits followed by “ENT”.

e.g.

If the frequency entered is less than 490.0 KHz

or greater than 29999.99 KHz, the radio will

prompt “ILLEGAL” and revert to the last

channel entered.

When trying to transmit on a receive only

frequency, the display will show “RX ONLY”.

will not operate in receive only mode.

SELECTING THE EMERGENCY CHANNEL

Press

The radio will switch to the international

emergency frequency of 2182.0 KHz using

USB, J3E mode.

If H3E (AME) mode is required, press

repeatedly until “MODE” is displayed.

Press then or

(“PRESS+-”) repeatedly until “AME” appears.

Press

The radio is now ready to transmit an AME

signal using a 40 W carrier.

Pressing the will briefly show the

assigned channel number, “EMER 0”. LOW AME

LOW AME

LOW

2182

2182 0

2182 ENT1

FNC

ENT

LOW

GENERAL OPERATIONS

UP DN

SENDING THE DISTRESS ALARM SIGNAL

Press to stop any entry in progress.

Press to select 2182.0 KHz.

If H3E (AME) mode is required, press

repeatedly until “MODE” is displayed.

Press then the or key

repeatedly until “AME” appears.

Press to select AME mode.

AME is only available on 2182.0 KHz.

To transmit the alarm signal, hold the

key down then press

The radio will transmit the alarm for 45

seconds unless stopped by pressing

The two tone alarm signal can be transmitted

on all available frequencies. It is not necessary

to use 2182.0 KHz for the alarm generator to

function.

To test the alarm without transmitting a signal,

press

You will hear the alarm tones through the

speaker but no signal will be transmitted. This

will continue for 45 seconds unless stopped by

again pressing LOW AME

TX TND

LOW AME

ENT

FNC

ENT

ALRM

SEND

2182

ALRM

LOW

LOW AME

GENERAL OPERATIONS

2UP DN

OVERRIDE

When operating conditions are outside the normal preset limits, the radio will

revert to low power (approximately 75 Watts). The display’s “LOW” indicator

will light to indicate this condition. If this

should occur during an EMERGENCY

situation, pressing

will override the monitoring sensors and allow

FULL output power. The radio will stay in the

EMERGENCY OVERRIDE condition until the

radio power is re-cycled. If the power has been reduced manually or the tuner

fails to match the antenna, the override will not increase to full power.

SQUELCH OPERATION

Use the key to toggle the squelch

on / off. The “SQL” indicator shows the

squelch is on. The speaker will mute after

approximately 2 seconds. Varying audio

frequencies will open the squelch but not a

steady tone.

CLARIFIER OPERATIONS

In the “MARINE” operating system, the

clarifier tuning range is limited to ±200 Hz

when used on any Bin or ITU/SEA channel.

When the radio is turned on, the clarifier step

size will default to 10 Hz.

Any “receive only” frequency or any frequency

used in the “AMATEUR” operating system has

an unlimited clarifier range and can be changed

in steps of 10 Hz, 100 Hz, 1 KHz, or 10 KHz.

To change the clarifier resolution:

Select “1” for 10 Hz steps, “2” for 100 Hz

steps, “3” for 1 KHz steps or “4” for 10 KHz

steps then “UP” or “DN”.

e.g. Press or to have the clarifier change in 100 Hz steps.

The chosen clarifier digit will blink for 2 seconds to indicate the selection. If the

digit does not blink, it is not a valid selection for the current mode and the

setting will not change .

TND SQL

SQL

6FNC6

TND SQL

Flashing clarifier set for 10 Hz (default)

LOW SQL

Flashing clarifier set for 10 KHz

GENERAL OPERATIONS

OPERATING THE MEMORY BROWSE

Browse enables a manual scan of all channels

or bins programmed in the radio.

Press then or

Pressing will change the channel to the

next channel in memory. The display will then

change to frequency mode when an ITU/SEA

channel is selected.

Pressing will change the channel to the

previous channel in memory. The display will

then change to frequency mode when an

ITU/SEA channel is selected.

will toggle between bin/channel,

frequency and name tag display modes.

Memory browse will not scan through bins and

channels at the same time. If a channel is

selected and you wish to browse the bins, select

a bin number from which to start.

When the last bin or channel is selected, the next step will go to the beginning of

the bin or channel list.

To exit memory browse, press the microphone Push To Talk button briefly,

adjust the clarifier step size or recycle the radio power.

LOW

Starting at ITU channel 403

Next ITU channel in memory is 404

LOW

Previous ITU channel in memory is 402

LOW

ADVANCED OPERATIONS

SELECTING THE PROGRAM MENU

To enter the program mode

press

The display will show “PROGRAM”, followed

by the first program option. Every time the

key is pressed, the radio will step to the next programming menu

option. The options available for programming are “STORE”, “ERASE”,

“ALPHA” and “EXIT”.

“STORE” will allow saving either the displayed information or entering a new

transmit / receive frequency pair and operating mode. If a name tag other than

the suggested is used (other than “NEW”), a new scan cell will be created.

“ERASE” deletes the bin number entered. Erasing a bin will split a scan cell.

“ALPHA” is the name tag edit routine. This routine is also used when storing a

display or new frequency pair.

“EXIT” will exit the program menu. No channel or frequency information will

be stored when EXIT is selected.

NOTE: Care should be given to the bin number used when programming frequencies.

The bin number and name tag will affect how channels are browsed and scanned.