MFJ SlimLine MFJ-441 User manual

SlimLine ECONO KEYER
with MEMORY
MODEL MFJ-441
OWNER'S MANUAL

MFJ-441 Instruction Manual
SlimLine Econo Keyer
1
Introduction
The MFJ-441 SlimLine™ Econo Keyer with Memory is a microprocessor controlled keyer that pro-
vides iambic key operation and dot-and-dash memory to make sending perfect code easier. It has
tuneable 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 mo-
mentary push-button that is time sensitive.
4. The Speed control varies the code speed. The speed range is configured with an internal
jumper (JMP 9) 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 JMP 9 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 stand-
ard dot defined as 50 % weight. The standard dot-dash-space 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-clockwise to lower the pitch. This control is lo-
cated 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, flat-headed
screwdriver.
7. The Volume control adjusts the sidetone level of the internal speaker. Turn the control clock-
wise to increase the volume and counter-clockwise to decrease the volume.
8. The Direct/Grid-Block Output keying circuit allows keying of grid-block 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 direct keying. To change to grid-block keying
the power must be off, then remove the cover by removing the two screws (one on each side)
that secure it. Locate JMP 1 and JMP 2. JMP 2 is directly behind the RCA jack and JMP 1 is ap-
proximately one inch in front of JMP 2. Set both jumpers JMP 1 and JMP 2 to the "G" position.

MFJ-441 Instruction Manual
SlimLine Econo Keyer
2
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 JMP 3 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 ele-
ment. Type "A" just finishes the element in progress and does not produce a following alter-
nate element. For example, in Type "A" Iambic, a squeeze release during the "dah" in the letter
A will produce "di-dah" (A). In Type "B" Iambic, a squeeze release during the "dah" in the let-
ter A will produce "di-dah-dit" (R).
Installation
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 pro-
vided for installing a 9-volt battery.
2. A 12 VDC power supply may also be used to power the MFJ-441. A 2.1 mm 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 ca-
bles 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 be-
comes 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 connection 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.

MFJ-441 Instruction Manual
SlimLine Econo Keyer
3
Keyer Operation
1. A 9-volt battery or an optional dc adapter may be used to supply power to the keyer.
2. The key paddle should be connected to the Key jack on the rear panel of the unit. A dual pad-
dle 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 al-
ternate 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" (dah-dah-dit dah-dah-dah) in Morse code and
the LED flashes. 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 Mes-
sage 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 charac-
ter. The speed, weight and tone cannot be changed during message recording. Also, the output
keying circuit is disabled during recording.
Note: A straight or manual key cannot be used to record the message.
To play the recorded message, momentarily press the Message button. Ongoing message can be
stopped by tapping either paddle or pressing the Message button. The memory is set up 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.

MFJ-441 Instruction Manual
SlimLine Econo Keyer
4
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: UR RST 559 559 SN /N /D SN /N
/G# Gap – inserts a gap of # standard intra-character spaces into the message, where # is a
digit in the range of 1 to 9 (0 can be used but not practical). Invalid numeral code will auto-
matically 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: BEACON DC7XJ 5 W /L
/N Number – inserts a contest serial number, in the range of 001 to 9999, into the message.
Jumpers JMP 4 to JMP 8 controls the way zeros and nines in the serial number are sent.
Only three digits are sent for numbers less than 1000 - use leading zeros when appropri-
ate. 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 not used. The serial number reset
to 0001 when power on. If a different serial number is desired, it must be programmed dur-
ing power up. To initialize the serial number, press and hold the Message button while turn-
ing the power on until the keyer plays "GO" (dah-dah-dit dah-dah-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-dah-dah-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: YOU ARE CONTACT NR /N
/Pmmss Pause – inserts a timed pause of mm minutes and ss seconds into the message.
Four numbers must follow "/P". Invalid numeral code will automatically default to zero.
Example: TIMEOUT 1 HOUR /P6000
TIMEOUT 1.5 MIN /P0090
TIMEOUT 1 HR 40 MIN 39 SEC /P9999
/R Resume – suspends message playback to allow insertion of paddle entry. 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.

MFJ-441 Instruction Manual
SlimLine Econo Keyer
5
Jumper Settings
JMP 1
JMP 2
Keying Mode
D
D
Direct *
D
G
Invalid
G
D
Invalid
G
G
Grid Block
JMP 3
Iambic Mode
A
A *
B
B
JMP 4
JMP 5
Leading Zeros
L
L
none
L
H
0
H
L
O *
H
H
T
JMP 6
JMP 7
Other Zeros
L
L
0 *
L
H
0
H
L
O
H
H
T
JMP 8
Nines
L
9 *
H
N
JMP 9
Speed Range
L
5 – 65 WPM *
H
10 – 40 WPM
* Factory defaults

MFJ-441 Instruction Manual
SlimLine Econo Keyer
6
Self Test
A self test is included to perform testing of the paddle, the buttons, the controls, and the audio cir-
cuitry. 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 comfort-
able listening level.
4. Remove the box cover (2 screws).
5. Remove jumpers JMP 4 to JMP 7. Set jumper JMP 3 to the "B" position. Set jumpers JMP 8 and
JMP 9 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 "COPYRIGHT 1996-199X MFJ ENTERPRISES, INC. VERSION X.XX" confirming the
audio circuitry is working properly. 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 JMP 3 to JMP 9 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 JMP 3 and
then the "L" positions of JMP 4 to JMP 9 in ascending order. The LED should blink once for
each jumper.
15. When all is okay, a repetitive message "PASS" is sent to the speaker. A repetitive message such
as "SP FAIL" indicates that you did not follow the correct order or the unit failed the test.
16. Turn 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:
DH FAIL Dash level is shorted or improperly connected.
DT FAIL Dot level is shorted or improperly connected.
J3 FAIL Jumper JMP 3 is shorted or improperly connected.
J4 FAIL Jumper JMP 4 is shorted or improperly connected.
J5 FAIL Jumper JMP 5 is shorted or improperly connected.
J6 FAIL Jumper JMP 6 is shorted or improperly connected.
J7 FAIL Jumper JMP 7 is shorted or improperly connected.
J8 FAIL Jumper JMP 8 is shorted or improperly connected.
J9 FAIL Jumper JMP 9 is shorted or improperly connected.
MG FAIL Message button is shorted or improperly connected.
SA FAIL Semi-Auto/Auto button is shorted or improperly connected.
SP FAIL Speed control is bad.
TN FAIL Tone control is bad.
WT FAIL Weight control is bad.

MFJ-441 Instruction Manual
SlimLine Econo Keyer
7
Morse Code Character Set
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 ·····
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 –––––
Period [.] di-dah-di-dah-di-dah ·–·–·– AAA
Comma [,] dah-dah-di-di-dah-dah ––··–– MIM
Question Mark or Request for Repetition [?] di-di-dah-dah-di-dit ··––·· IMI
Fraction Bar or Slash Bar [/] dah-di-di-dah-dit –··–· DN
End of Message, Plus Sign or Cross [+] di-dah-di-dah-dit ·–·–· AR
End of Work di-di-di-dah-di-dah ···–·– SK
Double Dash, Equal Sign, Pause or Break [=] dah-di-di-di-dah –···– BT
Semicolon [;] dah-di-dah-di-dah-dit –·–·–· KR
Colon [:] dah-dah-dah-di-di-dit –––··· OS
Apostrophe ['] di-dah-dah-dah-dah-dit ·––––· WG
Quotation Mark ["] di-dah-di-di-dah-dit ·–··–· AF
Hyphen or Dash [-] dah-di-di-di-di-dah –····– DU
Underline [_] di-di-dah-dah-di-dah ··––·– IQ
Dollar Sign [$] di-di-di-dah-di-di-dah ···–··– SX
Left Parenthesis or Go Only [(] dah-di-dah-dah-dit –·––· KN
Right Parenthesis [)] dah-di-dah-dah-di-dah –·––·– KK
Wait or Stand By di-dah-di-di-dit ·–··· AS
Understood di-di-di-dah-dit ···–· SN
Starting Signal dah-di-dah-di-dah –·–·– KA
Error di-di-di-di-di-di-di-dit ········ HH
Paragraph [¶] di-dah-di-dah-di-dit ·–·–·· AL
Invitation to Transmit or Go Ahead dah-di-dah –·– K
Signals Used In Other Radio Services
Interrogatory di-di-dah-di-dah ··–·– INT
Emergency Silence di-di-di-di-dah-dah ····–– HM
Executive Follows di-di-dah-di-di-dah ··–··– IX
Break-in Signal dah-dah-dah-dah-dah ––––– TTTTT
Emergency Signal di-di-di-dah-dah-dah ···––– SOS
Relay of Distress dah-di-di-dah-di-di-dah-di-dit –··–··–·· DDD

MFJ-441 Instruction Manual
SlimLine Econo Keyer
8
Schematic