CWirc QRSS extension

CWirc QRSS extension

What is it ?

This is a patch that enables glfer to become an extension of CWirc, to do QRSS CW over IP.

In the ham radio world, QRSS is very slow CW, meaning Morse code sent at very low speed in order to conserve bandwidth and concentrate the emitted power on the signal. On the receiving end, specialized software, like glfer, does signal processing with FFTs to help the operator pick the signal out of the background noise and display it in a slow-moving waterfall to make the Morse code easily apparent despite the long transmission times. QRSS is useful on very low bands, where the bandwidth for full speed CW isn't available, or when conserving bandwidth is of the essence, in low-power situations for example.

Why do QRSS on the internet ?

Indeed, since the internet has none of the bandwidth limitations of low-power or lower-band radio to hinder transmission speeds, one may wonder why anyone would want to wait minutes or even hours to send a short message, and have to wait as long for the reply.

Well, the interest is multifold: if you're a ham and you don't have access to the exotic bands where QRSS is usually practiced, and you're curious to see how such QSOs are made, glfer with CWirc can provide a somewhat realistic simulation. You may also want to use it to adjust the glfer sampling rate and/or transmitting rate to your liking online, then hit the airwaves with a perfect setup. If you're into signal processing, it can also provide you with a controlled environment where you can test glfer with different levels of QRN, Morse code speeds, simulated propagation and signal fading,... Finally, if you're a ham without a shack, this provides you with the ability to try out QRSS despite the odds.

Just like Echolink, which isn't real radio but has interest of its own, QRSS over IP is just another ham-related activity (albeit, admittedly, a slightly strange and obscure one) to play with when the bands are down.

What you need

- A Linux, FreeBSD or NetBSD system with CWirc installed
- The glfer spectrogram viewer and QRSS/DFCW transmitter
- The CWirc extension mode patch for glfer

How to set up CWirc and glfer

- Install and configure CWirc. Please refer to the CWirc manual for details.
- Download, and untar the glfer archive
- Apply the CWirc extension mode patch to the glfer source tree
- Build and install glfer normally with ./configure ; make ; make install as root.

- Make CWirc aware that it can use glfer as an extension program by making a symlink to where the glfer binary was installed into the CWirc extension directory. For example, if glfer is in /usr/local/bin and the CWirc extension directory is /usr/lib/cwirc/extensions, invoke the following command as root:

ln -s /usr/local/bin/glfer /usr/lib/cwirc/extensions/QRSS

Then, start (or restart) CWirc. A new tab should appear in the CWirc panel, containing a button with the name of the symlink you made to glfer (in the example above, "QRSS").

Using glfer with CWirc

Start X-Chat and CWirc, and join a suitable CWirc IRC channel like you normally would to do regular Morse. Click on the new extension button in the CWirc panel to start glfer in slave mode.

In slave mode, glfer receives sound from CWirc no matter what the sound device settings are, and any external PTT device is disabled. If you also use glfer normally however (i.e. not just with CWirc), running it in slave mode doesn't modify your settings at all.

Once glfer is started, you can start trafficking in QRSS normally as you would with a real radio transceiver. Note that the DFCW mode doesn't work with CWirc, as it is not an on/off keyed mode.

Sending QRSS Morse with CWirc

- Set the channel you want to send to in the CWirc panel

- Set the dot length in ms corresponding to the speed you want to send at in the "Settings -> QRSS" menu. Also ensure that the mode is set to "QRSS"

- Select "QSO -> Message" in the menu, type the message to send and click on "Start"

Receiving QRSS Morse with CWirc

- Set the channel you want to receive from in the CWirc panel

- In the "Settings -> Spectrum -> Acquisition" menu, set a sample rate appropriate to the expected speed of the reply

- When the incoming Morse beeps arrive, they are displayed in the form of horizontal lines and breaks in the display, that you can decode visually

Using QRN and propagation simulation

To simulate a real QRSS QSO more realistically, try enabling QRN, propagation and sporadic-E simulation in CWirc : depending on where the other parties on the IRC channels are (and if they send their grid locations in their signal), you'll see degraded or fading lines, noise, and if there is more than one sender at a time, you'll see multiple lines stacked up, corresponding to each sender's transmission.

Where to find active CWirc channels

- Channels containing "cwirc"

Note: if you create a channel, please put "CWirc" somewhere in the channel name or topic so it can be listed on SearchIRC

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