MFJ MFJ-441 User Manual

MFJ-441 Instruction Manual SlimLine Econo Keyer

Introduction

The MFJ-441 SlimLine™ Econo Keyer with Memory is a microprocessor
controlled keyer that provides iambic key operation and dot-and-dash memory to
make sending perfect code easier. It has tunable code speed, code weight, and
sidetone frequency; it supports both direct and grid-block keying outputs. You
also get to choose between Iambic Type "A" and Type "B" keying. It even has a
volatile memory to record and play a message of your choice.

Control Functions

1. The Power button turns the unit ON and OFF. The power is ON when the

button is locked in the "in" position and OFF in the "out" position.

2. The Semi-Auto/Auto button allows semi-automatic "bug" and manual

operations. The keyer generates dots automatically when a squeeze or
single lever key is used. Dashes are manually made. The keyer is
completely manual when a straight key is used. Semi-Auto is active when
the switch is in the "in" position and Auto when in the "out" position.

3. The Message button lets you record and play a message from the volatile

memory. It is a momentary push-button that is time sensitive.

4. The Speed control varies the code speed. The speed range is configured

with an internal jumper (JMP9) for 5 to 65 WPM or 10 to 40 WPM. Turn
the control clockwise to increase speed and counter-clockwise to decrease
speed. The unit is factory set to 5 to 65 WPM. To make the speed
adjustment less sensitive, change the speed range to the narrower range of
10 to 40 WPM. To change the speed range the power must be off, then
remove the cover by removing the two screws (one on each side) that secure
it. Locate jumper JMP9 and set it to the "H" position.

Note: Power must be off when changing the jumper settings.

5. The Weight control varies the code weight from approximately 25% to

75%, with the standard dot defined as 50% weight. The standard dot-dash­space ratio is 1:3:1 (trimpot at mid-range). Turn the control clockwise to
increase dot and dash lengths and counter-clockwise to decrease dot and
dash lengths. This control is located internally. When looking at the unit's
front panel, it is accessible through the small hole on the left side, closest to
the rear and may be adjusted by inserting a small, flat-headed screwdriver.

6. The Tone control sets the desired sidetone pitch from approximately 300 to

1200 Hz. Turn the control clockwise to raise the pitch and counter-

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MFJ-441 Instruction Manual SlimLine Econo Keyer

clockwise to lower the pitch. This control is located internally. When
looking at the unit's front panel, it is accessible through the small hole on the
left side, closest to the front and may be adjusted by inserting a small, flat­headed screwdriver.

7. The Volume control adjusts the sidetone level of the internal speaker. Turn

the control clockwise to increase the volume and counter-clockwise to
decrease the volume.

8. The Direct/Grid-Block Output keying circ uit allows keying of grid-bl ock

and solid state transmitters. The MFJ-441 can only key one type of
transmitter at a time. This is an internal jumper selected option. The unit is
factory set to d ire ct keying. T o change t o gri d-bl ock ke ying the power must
be off, then remove the cover by removing the two screws (one on each
side) that secure it. Locate JMP1 and JMP2. JMP2 is directly behind the
RCA jack and JMP1 is approximately one inch in front of JMP2. Set both
jumpers JMP1 and JMP2 to the "G" position. To key a solid state
transmitter, set both jumpers to the "D" position.

Note: Power must be off when changing the jumper settings.

9. The Iambic Type A/B mode is also set inside the unit with a jumper. The

unit is factory set for Type "A" Iambic. If you prefer Type "B" Iambic,
remove the cover by removing the two screws (one on each side) that secure
it. Locate jumper JMP3 and set it to the "B" position. For Type "A"
Iambic, set the jumper to the "A" position.

Note: Power must be off when changing the jumper settings.

When a squeeze is released during an element (dot or dash), type "B" adds
the opposite element. Type "A" just finishes the element in progress and
does not produce a following alternate element. For example, in Type "A"
Iambic, a squeeze release during the "dah" in the letter A will produce "di­dah" (A). In Type "B" Iambic, a squeeze release during the "dah" in the
letter A will produce "di-dah-dit" (R).

Installation

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MFJ-441 Instruction Manual SlimLine Econo Keyer

1. A 9-volt battery (not included) may be installed. Remove the cover by
removing the two screws (one on each side) that secure it.. A battery holder,
located inside the enclosure, is provided for installing a 9-volt battery.

2. A 12 Vdc power supply may also be used to power the MFJ-441. A 2.1mm
coaxial plug with a positive center and a negative sleeve should be used to
power this unit. The MFJ-1312B, an optional 12 volts adapter, is available
from MFJ Enterprises, Inc. The battery is automatically disconnected when
external power is used.

3. A squeeze or single lever key can be used. Squeeze key allows Iambic
operation. A 1/4-inch stereo phono plug and a two-conductor shielded cable
should be used. If separate shielded cables are used, the two shields should
be tied together and connected to ground. The dot wire should be connected
to the tip of the plug and the dash wire to the ring. The MFJ-441 becomes a
manual keyer when a straight key is used. The unit will safely key your
transmitter and eliminate the shock hazard of high voltage being present on
the straight key.

Note: To use a straight key, first switch the keyer to the Semi-Auto mode

(button in). Again a 1/4-inch stereo phono plug should be used
because a mono plug will not work on a straight key in Semi-Auto
mode. Connect one wire to the ring of the plug and another wire to
ground. The tip of the plug should not used.

4. Output keying circuit allows keying of grid-block and solid state
transmitters. Remember this is internally jumper selected (refer to page 2).
The keying output c onnection is made with a RCA phono plug.

Note: Consult the transmitter's instruction manual to determine which

output to use. When in doubt, try both jumper positions. The
transmitter will key continuously when the jumpers are connected to
the wrong positions.

Keyer Operation

1. A 9-volt battery or an optional dc adapter may be used to supply power to
the keyer.

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MFJ-441 Instruction Manual SlimLine Econo Keyer

2. The key paddle should be connected to the Key jack on the rear panel of the
unit. A dual paddle squeeze key or a single lever key can be used.

3. Next, the keyer should be turned on with the Power switch.

4. The Semi-Auto/Auto switch should be in the "out" position for automatic
operation.

5. The user should now start sending with the paddle and adjust volume, tone,
weight, and speed to his or her preference.

6. The dot and dash memories make sending easier. The memories allow the
user to key a dot before the completion of a dash and vice versa. This
feature can be checked by setting the keyer to the lowest speed and tapping
first the dash lever and then the dot lever before the completion of the dash.
The keyer will provide both the dash and the dot. The dash memory can be
checked in a similar manner. The dot insertion feature allows the user to
insert a dot by tapping the dot lever while holding the dash lever in. The
dash insertion feature allows the user to insert a dash while holding the dot
lever in. The Iambic operation allows sending of alternate dots and dashes
when using squeeze key and with both paddles squeezed. The first paddle
contacted will determine whether a dot or dash occurs first.

7. The user may select either Iambic A or B according to his preference.

Message Memory

The Message button is used to record and play your message. To record the
message, press and hold the Message button until the keyer plays "GO" (dah­dah-dit dah-d ah-dah) i n Morse c ode and the LED fla shes. You may now key in
the message of your choice. As you pause after every word, the keyer will play a
"W" (di-dah-dah) over the sidetone speaker to show that it is inserting a word
break (uses one unit of memory). If you make a mistake entering a word, you
can back up over it by briefly pressing and releasing the Message button. The
keyer will erase the last word, then play the word before it (if any) to let you
know where you stopped. If deleting the first word of the message, the keyer
will play "GO" instead. At the end of your message, press and hold the Message
button until the keyer sends an end of message character "+" (di-dah-di-dah-dit)
and the LED stops flashing. When there are ten or less units of memory
remaining, the LED will flash faster to let you know the memory is running low.
If you try to save more characters than you have memory, the keyer will
automatically end your message and send you an end of message character. The

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MFJ-441 Instruction Manual SlimLine Econo Keyer

speed, weight and tone cannot be changed during message r ecord ing. Also, the
output keying circui t is disabled during recor ding.

Note: A straight or manual key cannot be used to record the message.

To play the recorded message, momentarily press the Message button. On-
going message can be stopped by tapping either paddle or pressing the Message
button.

The me mory is s e t u p for only one message and it is volatile; that is, when power
is removed the message is erased. There are 85 units of memory, which can
record up to 85 characters (nine elements maximum per character--an element is
a dot or a dash). Each normal character uses one unit of memory; only the rarely
used 7-, 8- and 9-element characters require two units of memory.

Embedded Commands:

While in the message recording mode you may use embedded commands for
special features. To use an embedded command simply store the multi-character
embedded command code within your message.

/D

Decrement−decrements the serial number. Serial number 0001 will

decrement to 9999, skipping 0000 since it is not used. This feature
allows a serial number to be sent twice in a message.

Example:

/G#

Gap−inserts a gap of # standard intra-character spaces into the message,

UR RST 559 559 SN /N /D SN /N

where # is a digit in the range of 1 to 9 (0 can be used but not practical).
Invalid numeral code will automatically default to zero. This command
is used to exaggerate inter-character and word spacing.

/L

Loop−creates a message loop (message repeat). Note that any character

recorded after "/L" will not be sent.

Example:

/N

Number−inserts a contest serial number, in the range of 001 to 9999,

BEACON AA5CS 5 W /L

into the message. Jumpers JMP4 to JMP8 controls the way zeroes and
nines in the serial number are sent. Only three digits are sent for
numbers less than 1000--use leading zeros when appropriate. The
serial number is automatically post-incremented each time it is sent.
Serial number 9999 will wrap-around to 0001, skipping 0000 since it is

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MFJ-441 Instruction Manual SlimLine Econo Keyer

not used. The serial number reset to 0001 when power on. If a
different serial number is desired, it must be programmed during power
up. To initialize the serial number, press and hold the Message button
while turning the power on until the keyer plays "GO" (dah-dah-dit dah­dah-dah) and the LED flashes. You must then enter four numbers in
Morse code for a valid serial number, most-significant digit first
(invalid numeral code will automatically convert to zero). All numbers
must be in the proper Morse code format. For example, the number "1"
must be "di-dah-dah-dah-dah" and the number "0" must be "dah-dah­dah-dah-dah". When four numbers are entered, the keyer will
automatically send an end of message character "+" (di-dah-di-dah-dit).
The keyer then resumes with normal operation when the LED stops
flashing. The serial number can be set from 0000 to 9999 (0000 will
automatically convert to 0001).

Example:

/Pmmss

Pause−inserts a timed pause of mm minutes and ss seconds into the

YOU ARE CONTACT NR /N

message. Four numbers must follow "/P". Invalid numeral code will
automatically default to zero.

Example:

HR 40 MIN 39 SEC /P9999

/R

Resume−suspends message playback to allow insertion of paddle entry.

TIMEOUT 1 HOUR /P6000 TIMEOUT 1.5 MIN /P0090 TIMEOUT 1

Once paddle sending is finished, press the Message button again to
continue the message.

/S

Space−inserts an extra standard word space into the message. This

command yields the same result as "/G7" but uses one less unit of
memory.

//

Slash character−stores the slash character "/" into the message.

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MFJ-441 Instruction Manual SlimLine Econo Keyer

Jumper Settings

JMP1 JMP2 Keying Mode

D D Direct *
D G Invalid
G D Invalid
G G Grid Block

JMP3 Iambic Mode

A A *
B B

JMP4 JMP5 Leading Zeroes

L L none
L H 0
H L O *
H H T

JMP6 JMP7 Other Zeroes

L L 0 *
L H 0
H L O
H H T

JMP8 Nines

L 9 *
H N

L 5 - 65 WPM *
H 10 - 40 WPM

JMP9 Speed Range

* Factory defaults.

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MFJ-441 Instruction Manual SlimLine Econo Keyer

Self Test

A self test is included to perform testing of the paddle, the buttons, the controls,
and the audio circuitry. At any time, turn off the power to stop the self test.

To perform this test:

1. Turn off the power and remove the power plug.

2. Push all buttons so they are in the out position.

3. Turn all knobs to full clockwise position, except the Volume control. Set
volume to a comfortable listening level.

4. Remove the box cover (2 screws).

5. Remove jumpers JMP4 to JMP7. Set jumper JMP3 to the "B " po sition. Set
jumpers JMP8 and JMP9 to the "H" position.

6. Reconnect power.

7. Squeeze the paddle while turning the power on. The self test starts by
sending the copyright message

INC. VERSION X.XX"

confirming the audio circuitry is working properly.

"COPYRIGHT 1996-199X MFJ ENTERPRISES,

Release the paddle before the message is finished. For the entire test, the
LED should blink once after each operation. If the LED blinks continuously
the unit fails the test and a Morse code message is sent to indicate the nature
of the failure.

8. The paddle, the Message button, and jumpers JMP3 to JMP9 are
automatically tested for shorts to ground. The LED should be off at this
point.

9. Press and release the dot level; press and release the dash level.

10. Press and release the Message button.

11. Lock in the Semi-Auto/Auto button, then press and release the dash level.

12. Test the Speed control by turning it to full counter-clockwise then to full
clockwise. The LED should blink once at each end.

13. Test the Weight and Tone controls in the same way. The LED should blink
once at each end.

14. Test the jumper connections by placing the plug-in jumpers on the "A"
position of JMP3 and then the "L" positions of JMP4 to JMP9 in ascending
order. The LED should blink once for each jumper.

15. When all is okay, a repetitive message
repetitive message such as

"SP FAIL"

"PASS"

is sent to the speaker. A

indicates that you did not follow the

correct order or the unit failed the test.

16. T urn off the power after confirming the audio has good quality and remove
the power plug.

17. Replace all jumpers to their original positions.

18. Replace the cover and secure it with the two (2) screws.

19. Reconnect power and resume with normal operation.

Failure Message Meanings:

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MFJ-441 Instruction Manual SlimLine Econo Keyer

DH FAIL

•

DT FAIL

•

J3 FAIL

•

J4 FAIL

•

J5 FAIL

•

J6 FAIL

•

J7 FAIL

•

J8 FAIL

•

J9 FAIL

•

MG FAIL

•

SA FAIL

•

SP FAIL

•

TN FAIL

•

WT FAIL

•

Dash level is shorted or improperly connected.
Dot level is shorted or improperly connected.
Jumper JMP3 is shorted or improperly connected.
Jumper JMP4 is shorted or improperly connected.
Jumper JMP5 is shorted or improperly connected.
Jumper JMP6 is shorted or improperly connected.
Jumper JMP7 is shorted or improperly connected.
Jumper JMP8 is shorted or improperly connected.
Jumper JMP9 is shorted or improperly connected.
Message button is shorted or improperly connected.
Semi-Auto/Auto button is shorted or improperly connected.
Speed control is bad.
Tone control is bad.
Weight contr ol is bad.

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MFJ-441 Instruction Manual SlimLine Econo Keyer

Morse Code Character Set

1

A di-dah
B dah-di-di-dit
C dah-di-dah-dit
D dah-di-dit
E dit
F di-di-dah-dit
G dah-dah-dit
H di-di-di-dit
I di-dit
J di-dah-dah-dah
K dah-di-dah
L di-dah-di-dit
M dah-dah

1 di-dah-dah-dah-dah
2 di-di-dah-dah-dah
3 di-di-di-dah-dah
4 di-di-di-di-dah
5 di-di-di-di-dit

Period [.] di-dah-di-dah-di-dah
Comma [,] dah-dah-di-di-dah-dah
Question Mark or Request for Repetition [?] di-di-dah-dah-di-dit
Fraction Bar or Slash Bar [/] dah-di-di-dah-dit
End of Message, Plus Sign, or Cross [+] di-dah-di-dah-dit
End of Work di-di-di-dah-di-dah
Double Dash, Equal Sign, Pause, or Break [=] dah-di-di-di-dah
Semicolon [;] dah-di-dah-di-dah-dit
Colon [:] dah-dah-dah-di-di-dit
Apostrophe ['] di-dah-dah-dah-dah-dit
Quotation Ma rk ["] di-dah-di-d i-dah-dit
Hyphen or Dash [-] dah-di-di-di-di-dah
Underline [_] di-di-dah-dah-di-dah
Dollar Sign [$] di-di-di-dah-di-di-dah
Left Parenthesis or Go Only [(] dah-di-dah-dah-dit
Right Parenthesis [)] dah-di-dah-dah-di-dah
Wait or Stand By di-dah-di-di-dit
Understood di-di-di-dah-dit
Starting Signal dah-di-dah-di-dah
Error di-di-di-di-di-di-di-dit
Paragraph [¶] di-dah-di-dah-di-dit
Invitation to Transmit or Go Ahead [K] dah-di-dah

1.

FCC test requirement consists the 26 letters, the 10 numerals, the period, the comma, the question mark, AR, SK, BT and
fraction bar DN.

N dah-dit

−

•

O dah-dah-dah

−

•••

P di-dah-dah-dit

−•−

•

Q dah-dah-di-dah

−

••

R di-dah-dit

•

S di-di-dit

••−•

T dah −

−−

•

U di-di-dah

••••

V di-di-di-dah

••

W di-dah-dah

−−−

•

X dah-di-di-dah

−•−

Y dah-di-dah-dah

•−••

Z dah-dah-di-dit

−−

6 dah-di-di-di-dit

−−−−

•

7 dah-dah-di-di-dit

−−−

••

8 dah-dah-dah-di-dit

−−

•••

9 dah-dah-dah-dah-dit

−

••••

0 dah-dah-dah-dah-dah

•••••

•−•−•

−−••−−

••−−••

−••−

•−•−•

•••−•

−

•••

−•−•−

−−−

−−−−

•

•−••−•

−

••••

••−−•

•••−••

−•−−

−•−−•−

•−•••

•••−•

−•−•−

••••••••

•−•−••

−•−

−

−−−

•−−•

−−•−

•−•

•••

••

•••

−−

•

−••−

−•−−

−−

−

−−

−−−

−−−−

−−−−−

−

•

−

−

•

•••

•

−

−

−

•

K

•

−

−

••

••••

•••

••

•

AAA
MIM
IMI
DN
AR
SK
BT
KR
OS
WG
AF
DU
IQ
SX
KN
KK
AS
SN
KA
HH
AL

Signals Used In Other Radio Services

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MFJ-441 Instruction Manual SlimLine Econo Keyer

Interrogatory di-di-dah-di-dah
Emergency Silence di-di-di-di-dah-dah
Executive Follows di-di-dah-di-di-dah
Break-in Signal dah-dah-dah-dah-dah
Emergency Signal di-di-di-d ah-dah-dah -di-di-dit
Relay of Distress dah-di-di-dah-di-di-dah-di-dit

INT

−

••−•

−−

••••

−

••−••

−−−−−

−−−

•••

•••

−••−••−

••

HM
IX
TTTTT
SOS
DDD

Technical Assistance

If you have any problem with this unit first check the appropriate section of this
manual. If the manual does not reference your problem or your problem is not
solved by reading the manual you may call MFJ Technical Service at 662-323-
0549 or the MFJ Factory at 662-323-5869. You will be best helped if you have
your unit, manual and all information on your statio n handy so you can answer
any questions the technicians may ask.

You can also send questions by mail to MFJ Enterprises, Inc., 300 Industrial
Park Road, Starkville, MS 39759; by Facsimile to 662-323-6551; or by email to
[e-mail]. Send a complete description of your problem, an
explanation of exactly how you are using your unit, and a complete description
of your station.

Notes

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MFJ-441 Instruction Manual SlimLine Econo Keyer

Schematic

12