My QRSS beacon

QRSS is a method of sending very slow morse code. The advantage of this method of communication is that long communication distances can be covered using very low power and simple antennas.

The official term for the transmitting equipment is Manned Experimental Propagation Transmitter (MEPT). Continuous transmission is permitted within the terms of the amateur radio license as long as the station is manned.

The most popular band currently used for QRSS is 30m with all activity confined to a 100Hz segment starting at 10.140MHz.

My MEPT comprises the following equipment.

Transmitter

My transmitter was built from one of the excellent kits sold by Hans Summers. This will send out my callsign in very slow morse (approx 6 second dits) between 10.1400 MHz and 10.1401 MHz using a frequency shift of 4Hz (the transmitter is constantly keyed).

The output power of this unit is sent to 100 mW.

The antenna is currently a homebrew magnetic loop made from heliax (semi rigid coaxial cable).

The fan on top is the start of a project to make the whole assembly wind and solar powered.

The transmitter and batteries are housed within the siver box in the centre of the loop. The black box contains the tuning capacitor which is adjusted by moving the red screwdriver handle underneath. The meter on the front of the box measures the RF voltage across the capacitor plates. This is used for tuning purposes and the tuning cap is adjusted for the maximum voltage measured on the meter. The meter is switched out of circuit after the antenna has been tuned.

I think that the design could be optimised and will look into replacing the variable capacitor with a home brew fixed value capacitor with a very low resistance connection to the main radiating loop. The small green triangular coupling loop was originally 1/5 of the diameter of the main loop but is now about 1/4 of the diameter following a little experimetation. Although this loop is now a delta shape it does not appear to perform much differently when bent into a circular form.

Reports

Reception reports are always welcome please send to:

Here are some screen grabs from the MM0LER grabber in the north of Scotland.

In the above shot my signal can be seen between the two white lines in the middle of the screen. MM0LER's own signal is visible close to the bottom of the screen.

This is my sloping signal shortly after switching on my MEPT. The frequency takes a few minutes to stabalise.

Grabbers from all over the world can be found at http://digilander.libero.it/i2ndt/grabber/grabber-compendium.htm

Further information can be found on the Knights QRSS clipboard managed by ON5EX.