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QRSS

I've started playing with QRSS, inspired by getting involved with QMX and QCX and the QRP world. QRSS is something to use the equipment for while I'm not actively operating CW, and by either transmitting QRSS for other people to receive, or running a receive “grabber” for other people to observe, I'm helping with other people's experimental use of the hobby (and my own). I could continue using WSPR for similar ends, but I find QRSS much more human.

First Step

I need to be able to receive - never transmit if you can't receive first. I remember using Spectrum Lab in the past, on 500kHz for a grabber, and I knew it ran well under Wine on Linux. So I installed Spectrum Lab on my Linux shack laptop.

A bit of fiddling and I got it to display QRSS nicely.

Grabber

Receiving locally is nice, but the real fun comes from sharing the waterfall image via the internet…. a “grabber”

That just required setting Spectrum Lab to make regular screen captures, and to deposit them in a directory where they can be accessed by the Linux system easily.

And then a small bash script to send the file by SCP to my VPS webserver. 

#!/bin/bash
DIR=/home/g4slv/Screenshots
 
sleep 5
 
scp -P 2182 $DIR/capt.jpg g4slv@g4slv.info:
rm $DIR/capt.jpg

and on the VPS another bash script to rename the new capture to include a datestamp, and then to copy the new capture to the webserver, along with the date-stamped copy. 

#!/bin/bash
 
 
DATE=`date +%y%m%d_%H%M`
 
DIR=/home/g4slv
sleep 30
if [ -e capt.jpg ]
then
        cp capt.jpg capt_$DATE.jpg
        sudo mv $DIR/*.jpg /var/www/html/grabs/
fi

This makes sure I don't lose all the grabs, and can access them via the website, to look for interesting artifacts, or signals of interest.

Both scripts run every 10 minutes via Crontab. Each script has a sleep command to delay it's operation to allow the correct sequence of actions, and to give time for the SCP operation to upload the new capture file to the VPS.

QRSS TX

To set the QMX to operate as a QRSS beacon is a bit convoluted….

  • Protection
    • PA Max volts → 3V - this will give approx 1W
  • Messages
    • Message 1 → GM4SLV
  • Keyer (from single click of Menu key in normal operation mode) → 6 (dot = 6 seconds)
  • Beacon
    • Mode → FSKCW
    • Frequency → 10,140,050
    • Frame → 10 (repeat every ten minutes)
    • Start → 0 (start on minute zero)
    • Time → set to any random time, it's just used to start each TX cycle every “Frame” minutes. Absolute time isn't important.

Sending “GM4SLV” at 6-second dot takes about 7 minutes, and then there's 3 minutes of RX to allow the PA to cool down, and the cycle repeats every 10 minutes. I don't know if the RTC is accurate enough to allow for “stacking” to improve reception of my signals, without GPS time lock it might drift around a little?

Further Information

Page created : 08/07/26 11:44 BST

Page updated : 08/07/26 13:02 BST

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