Month: March 2014

I added some buttons, a command button to enter into command mode, in which you can enter various commands from your paddle, and two buttons for memory messages.

The red LED shows you are currently in command mode.

One thing I did not expect was that in command mode only the side-tone output is available to monitor your paddle manipulation. Right now, the square wave side-tone signal is ignored because I thought the tone from the rig is more agreeable.

I checked the IC-7410 service manual, which you can find easily with Google, to see if I can connect the keyer output signal from ATmega32u4 used in an Arduino Leonard board directly to the ELE-KEY inputs of my rig. The input signals are named “DOTK” and “DASHK”, and if you trace the lines, you will find that the both signals go directly into the Front CPU (M30622F8PGP microcontroller), to which the Vcc of 3.3V is supplied.

Actually, the voltage at the ELE-KEY inputs is measured to be around 3.3V. Since the Vcc of ATmega32u4 on the Leonard board is 5V, we need to use either a level converter, most simply with two resistors, or an open collector (drain) circuit. It seems that the latter is the preferred choice, because it is a more generic approach.

A small universal board is used to be plugged on top of the Arduino board. Such boards are called “shields” in Arduino terminology.

The red and black lines go to the rig (keyer output), and the yellow, green and black lines go to the paddle.

Since you have a full control over the keyer from your PC, there are no volumes nor switches on the “shield”.

Do not forget to uncomment the following line in “keyer_features_and_options.h”:

#define FEATURE_MEMORIES

to enable the memories feature.

The CW Keyer program by K3NG is very versatile, and if the Keyer is connceted to a PC with a USB cable, although it is not necessary to use the Keyer, you can issue a command or a message to be sent from the keyboard using any terminal emulator programs such as PuTTY.

A keying output buffer (2SC1815) is used to connect the Aruduino CW keyer to my rig. The two lines (red) go to the rig, and the three lines (green) go to the paddle.

The red trace is the keying output before inverted by the output buffer, and the yellow trace is the side-tone from the rig.

I tried the CW keyer program by K3NG. The two blue lines connected to the probes are for Keying Output and Side-tone, respectively. The green line goes to the GND, and two blue lines go to my paddle.

These are the waveforms when the paddle is squeezed. The red trace shows the Keying Output, and the yellow one is the Side-tone around 600Hz.

The last time I played with the Leonardo board was perhaps last summer, so I need to download the latest Arduino integrated development environment (IDE) software, ARDUINO 1.5.6-r2 BETA 2014.02.21, from: http://arduino.cc/en/Main/Software#.UxiCvT9_vee

http://blog.radioartisan.com/arduino-cw-keyer/

A CW keyer software by K3NG is available at the above link. The highlighted area (in yellow) shows just a small part of the source code.

I obtained this board some years ago. The Arduino development environment is offered to edit, compile, download and run your programs.

http://arduino.cc/en/Guide/Windows#.UxcpBD9_vec

If you prefer, you can also write your programs in more popular languages such as C.

There are many CW Keyer programs for Arduino. One example is:
http://blog.radioartisan.com/arduino-cw-keyer/

Or you can write your own program best suited for your purposes.