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MFJ-493 Instruction Manual
5
Keyboard Operation
When you plug in a standard IBM style AT keyboard, your keyer becomes a powerful keyboard
keyer. The MFJ-493 uses the alphanumeric keys (A - Z 0 - 9), the function keys (F1 - F12) the
space bar, the arrow keys, and the punctuation characters that have Morse equivalents. Prosigns
have been assigned to some of the other punctuation characters for quick operation. See the table
on page 19.
The operation of the keyboard is simple. Begin typing on the keyboard. Typed characters are sent
to key outputs at the code speed of the keyer. If a typing mistake occurs, the backspace key can
be pressed to erase the last character typed before it is sent. If you want to "flush" all the text that
has not yet been sent press Esc .
When typing speed is greater than the WPM code speed, characters will begin to fill a type ahead
buffer. The code sent to the radio and over the sidetone speaker will lag behind the typing of each
character. Most of the time this will not cause a problem. Only for very fast typists that send slow
code will the type ahead buffer fill significantly. The maximum size of the type ahead buffer is 80
characters. When the buffer fills to 70 characters the sidetone will lower. This is a signal to slow
typing speed because when the buffer fills to 80 characters each new keypress will be lost. It is
best to never type much faster than your code speed.
If you want to send a special prosign you can use the Alt key. Press and hold Alt , press and re-
lease the first character of the prosign, press and release the second character of the prosign, re-
lease Alt . This will remove the intercharacter space between two letters making it a prosign. Any
prosign can be made this way, even special local prosigns.
Keyboard Function Keys
Press a function key F1 - F8 to play a saved message. To record a message, press and hold the
Alt key, press a function key ( F1 - F8 ) and release Alt . The keyer will respond with "GO". Now
a message can be typed into memory. Use the embedded memory commands the same way as on
a paddle.
The F9 through F12 keys are used for other commands.
The F9 key enters the command mode. Enter a two character command just like in Menu Opera-
tion.
The F10 key enters speed set mode. Change speed with the left and right arrows or type in the
two digit speed in WPM. Press Esc to exit.
The F11 key engages the output tune. The 493 will key to tune your station. Press Esc to exit.
The F12 key decrements the serial number. The keyer will echo a "D" for each number decre-
mented.
Summary of Contents for Memory Keyer MFJ-493
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