Remote Station - CW Operation

I recently discovered a Windows program called 'Remote CW Keyer' by DL4YHF. See the link <here>.

The program runs at both the control side (the client) and the radio side (the server); it transfers hand sent CW (paddle or straight key) to a remote radio over a WAN or LAN and has inherent allowance for network latency and jitter. It can handle multiple clients e.g. a multi op environment.

Rather than sending ASCII characters from operator to radio (as is the case with many remote CW solutions), it sends a precisely timestamped sequence of 'key down / key up' commands i.e. it measures the length of each dash, dot and space and sends the timing information from the client to the server. What is sent by the operator at the client is exactly replicated at the server to send the CW.

There are several solutions around for the remote CW operation. The challenges they pose are usually one or two of:

• When used with a contest logger, the sidetone from contest macros is not available on the same audio output as the hand-keyed sidetone.

• When used with a software front-end to a radio (e.g. SmartSDR, Win4*Suite etc.), the hand-keyed sidetone is not available on the same audio output as the radio's audio.

• The Morse is interpreted locally (at the control side) and the ASCII characters sent over to the radio side. This does not compensate for individual keying styles - the CW has to be absolutely perfect to be interpreted corrrectly, otherwise the incorrect ASCII characters are sent to the radio-side and gibberish is sent.

The way I have configured the DL4YHF program overcomes all the above issues. 

As designed, the Morse key plugs into the operator's laptop/PC's serial port via a small interface circuit; the program runs on this PC in 'client' mode. At the radio side. the same program is configured in 'server' mode and an output from a serial port is used to key the radio, again via a small interface circuit. It will happily work using USB ports acting as virtual serial ports (FTDI).  The side-tone from locally keyed CW can output through any sound device on the client PC; choose the same device that the radio's audio comes from and you hear both, but switch the radio's own side-tone off.

I used this configuration for a while with my Flex 6600 + SmartSDR; I then started to look at keying from my contest logging program. The Winkey output on the contest logger can be pointed to SmartCAT's Winkey emulator and that works OK - the sidetone from both the contest macros and the hand-keyed CW was available on the same audio sound device. However if I wanted to inject hand-keyed CW into the macro-sent CW, I found the timing challenging. 

I decided that the best solution would be to feed both my paddle and the contest logger into a K1EL Winkey unit and then take the keyed output from the Winkey to the input of the DL4YHF program, configured for a straight key. The schematic is below, it works great.