MFJ-461 Pocket CW Reader, Version 0B
Copyright
2001 MFJ Enterprises, Inc.
Introduction to the MFJ Pocket CW Reader
Thank you for purchasing the MFJ-461 Pocket CW
Reader. The CW Reader is a pocket size Morse code
decoder that features:
•
Two-line 32-character LCD (liquid crystal display)
•
Auto track CW up to 99 WPM (words per minute)
•
140 characters volatile repeat buffer memory
•
Four scrolling display modes
Please read the following instructions before using the
CW Reader. If you still have questions after reading all
the instructions, please refer to the “Technical
Assistance” section.
List of Components
9. PLL Frequency
10. Battery Cover
8. Input Level
7. LCD Screen
Se
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In
REPEAT
Mic
Lock
POWER
CW Reader
MFJ-461
3. Serial Out
4. Audio In
6. Lock LED
5. Microphone
2. Repeat
1. Power
1.
Power Button
– Push button in to turn power ON.
Always turn power OFF when changing the battery.
2.
Repeat Button
– Push button momentarily to
display the last 140 characters enclosed within “[“
and “]”; push button again to exit repeat mode. Push
and hold the button for two seconds to rotate
through the four different display modes.
•
Mode 1
– Text will display from left to right along
the bottom line. When filled, that entire line will
display on the top line until the bottom line refilled
with the speed displayed on the right side (power-
on initial mode).
•
Mode 2
– Text will display from left to right along
the bottom line. When filled, that entire line
displays on the top line until the bottom line refills.
•
Mode 3
– Text will scroll from right to left along the
top line with the speed displayed on bottom line.
•
Mode 4
– Text will scroll from right to left along the
bottom line, then up and across the top line.
3.
Serial Out Jack
– A 3.5 mm jack for connecting the
Reader to the computer’s serial port to display CW
text on a monitor using a terminal software. Use an
MFJ-5161 serial cable. Set the terminal software to
19200 baud, 8 data bits, no parity, 1 stop bit, and no
flow control.
4.
Audio In Jack
– A 3.5 mm jack for inputting any
audio source. A plug in this jack disconnects the
built-in microphone.
5.
Microphone (Mic)
– Picks up audio signal from your
receiver. This microphone is disabled when a plug
is inserted into the Audio In jack.
6.
Lock Indicator LED
– Indicates signal lock when it
blinks in sync with the Morse code.
7.
LCD Screen
– Displays the CW text on the two-line
32-character LCD screen.
8.
Input Level Control
– Adjusts the audio input level.
Rotate right to increase input level.
9.
PLL Frequency Control
– Adjusts the PLL (phase
locked loop) frequency from about 500 to 1000 Hz.
Rotate right to decrease frequency. Factory set to
approximately 700 Hz.
10.
Battery Cover
– Remove cover to add or replace
the 9-volt battery (not included).
Installing Battery
Remove the battery cover on the back of the CW Reader
and insert a 9-volt battery. Use
only
fresh, high quality
batteries. Alkaline batteries are recommended.
Caution: Always make sure the power is off before
replacing the battery.
Battery life will vary depending on usage, so always
keep a spare on hand. When the LCD begins to fade,
the battery life is almost gone and you should replace
the battery as soon as possible.
Operation
Power on your receiver and tune it to find a clear, well-
sent Morse code signal. When you have found one,
power on the Reader and place its microphone near
your receiver’s speaker. If necessary, adjust the Input
Level control so that the Lock LED is blinking. Now tune
in the signal again to adjust its frequency (to match the
PLL frequency) until you get the maximum response
from the LED. Next, turn the Input Level control until the
LED is blinking in sync with the Morse code. Wait for the
LCD screen to start displaying something that makes
sense. Once it has tracked the signal, read the
messages as they scroll across the LCD screen. Repeat
these steps a few times to get the best response.
The Reader automatically locks on and tracks low and
high speed Morse code, decoding it up to 99 WPM. Its
initial power-on tracking speed is 20 WPM. It will take
some time to track an incoming signal or to re-track an
extremely slow signal after copying a fast one and vice
versa. If there is a lot of static, it will take time to track
slow signals. This is because the static appears to the
Reader as high speed Morse code.
There is a lot of sloppy code on the air and most
computers cannot read them. Do not expect this Reader
to do the incredible when it comes to copying Morse
code. Nothing can clean up and copy a sloppy fist,
especially with a weak signal and lots of QRM/QRN
(interferences). However, you will be quite pleased
when copying strong well-sent code, especially those
sent with electronic keyers. Farnsworth code* and
extremely negative weighted code will display with
spaces between each character. Finally, invalid
characters are displayed as block characters on the LCD
screen and as spaces on the computer monitor.
Prosigns (procedural signs) are enclosed within “<” and
“>” such as <AR> and <SN>.
When it is too noisy for microphone pickup or when you
do not want to
hear
CW, you can connect the Reader to
your receiver using the Audio In jack.
* Farnsworth code is where the dits and dahs are sent at a fast
rate and the character and word spaces are much longer.
Accessories
The following accessories are sold separately:
•
MFJ-26B: Soft leather protective pouch with clear
plastic overlay for LCD display, equipped with push
buttons and jacks openings, and pocket/belt clip.
•
MFJ-5161: A 3.5 mm to DB-9 RS-232 serial cable.
•
MFJ-5162: Receiver cable that connects the Reader
to your radio’s external speaker 3.5 mm jack.
Copyright Message and Firmware Number
Press and hold the Repeat button while turning the
power on. A copyright message and the firmware
version number will display across the LCD screen. The
Reader then returns to normal operation.
