AAØZZ EZKeyer III 23 November 2014
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Copyright 2014 AAØZZ
"M" - Receiver Mute Mode Toggle. Default is OFF.
Response is "M" when toggled ON and "O" when toggled OFF. When ON, the receiver mute
circuitry becomes operational. Then, when the paddle is closed (either DIT or DAH) the RX Mute
output is activated, "shorting" the mute jack output to ground. 7 ms later the transmitter output jack
is keyed, "shorting" its output to ground. After the appropriate DIT-time or DAH-time for the current
CW speed the transmitter is un-keyed and 7 ms later the receiver mute is un-keyed. Note that the
leading 7 mS is taken away from the DIT/DAH "ON" time. The mute is keyed for 7 ms after the
DIT/DAH paddle is released and extends into the “OFF” time. The overall speed is constant,
whether or not this feature is ON. See Appendix A for timing details.
"P" – Speed Pot / Paddles toggle. Default is Speed Pot.
Response is “SP” when toggled ON and “O” when toggled OFF. When the Speed Pot is active
the speed is controlled from minimum to maximum by turning the potentiometer. The maximum
speed when pot speed control is active is normally 55 WPM but can be limited to 32 WPM by
installing a jumper shorting pin 1 to pin 2 (No High) of header HDR1 on the PCB. The minimum
speed when pot speed control is active is normally 5 WPM but can be set to 15 WPM by installing
a jumper shorting pin 3 to pin 4 (No Low) of header HDR1 on the PCB. When the Speed Pot is
inactive the speed is controlled by the paddles. Then the “S” command (Set CW Speed) can be
used to set the speed or quick speed changes can be accomplished by tapping the paddles as
described in the “S” command section.
"S" - Set CW speed (between 5 and 55 WPM). Default is 15 WPM.
Keyer response is a DIT, requesting the first digit, followed by another DIT requesting the second
digit. A "T" may be entered instead of a zero. Response is a "?" if the input is invalid.
Quick speed changes can be done without using the “S” command. Simply press and hold the
command pushbutton (pushbutton #1) and then tapping the left (usually DIT) paddle or the right
(usually DAH) paddle. Each time the left paddle is tapped the speed increased by 2 WPM. Each
timethe right paddle is tapped the speed is decreased by 2 WPM. The keyer responds with a DIT
after each tap and speed change.
Note that the speed pot must be disabled ("P" command) for the "S" command to be operational.
"T" - Tune.
Key the output continuously. Continues until the user taps one of the paddles.
"U" - Autospace Mode Toggle. Default is OFF.
Response is "A" when turned ON, "N" when turned OFF. This is an aid for sending good CW.
When enabled you cannot, for example, send code with two DIT-size spaces between any two
Morse elements. If you try to send CW with two DIT-size spaces it will automatically add one more,
assuming you are trying to send a letter-space instead of the ideal DIT-size space between the
elements of a letter. It's rather hard to hear unless you slow way down and try it.
"W" - Report Morse speed.
The keyer reports the current speed.
"X" - Swap Paddles. Default is left paddle DAH and right paddle DIT.
The DIT and DAH paddles are reversed.
"1" Load User Message 1.
The user enters characters for message 1 one character at a time. The keyer sends a DIT,
requesting a character. After the character is entered and validated, the keyer responds with
another DIT requesting the next character, etc. If the user wants a space he just waits for another
DIT without entering any character (about 2 seconds), indicating the space was saved in the