The Weak Signal Propagation Reporter Network is a group of amateur radio operators using K1JT's MEPT_JT digital mode to probe radio frequency propagation conditions using very low power (QRP/QRPp) transmissions. The software is open source, and the data collected are available to the public through this site.

After being off air for a couple of years after my old Icom failed, I am back on the air. Started on WSPR about 12 hours ago.
My new rig is TS120S about 30 years old maybe more, but goes well. Am restricted to 20M by my antenna type, but thats fine it's always been the best band forever! Seems like I specialise in old gear, even the PC is about 10 years old and running XP.

Having played around with multiple power on successive WSPR transmissions, I am now transmitting two WSPR signals at different power levels simultaneously from the same transmitter. I have modified the WSPR code to encode two separate WSPR frames 100Hz apart at different amplitudes to create a single wav file that gets transmitted in the usual way. My tests overnight ran at 1W and 50mW. The idea is that one can't really make fair comparisons between signals transmitted at different times - since propagation and local noise levels vary minute by minute.

When I started toying with WSPR yesterday, I did not grasp the full number of uses WSPR would have in store me. Propagation is the obvious one, however testing different antennas and seeing the gain change shape and direction, seeing TX power levels and distance mapping, coax vs ladder Line loss/gain and having real data for differing radios TX and RX differences over time will really allow me (everyone) the ability to identify what works and whats just dreaming or guessing.

I'm using my FT-817ND at .5 watts into my main 20M vertical for this first test. I'll later construct a full wave loop antenna for 10M or 20M and assign this antenna and radio to WSPR. I'm also going to attempt to install/compile the WSPR software on my BeagleBone Black and also dedicate this set up to WSPR.

That is until I receive the Ultimate3 QRSS/WSPR kit in the mail and get that running, then I'll incorporate it into the WSPR set up..

I can see people's WSPR transmissions on my screen, I'll have to give it a bit and see if my TX was received as well.

According to web cluster, 6m condition seems good.
Now, beaming to North America.


Tonight, I upgraded the core content management system used by WSPRnet. Not everything is back to where it was, but I'm done for the night. I will clean up some of the formatting and presentation tomorrow. Thanks for your patience!

we are in Spain allow to TX in 4m. band from 70,150 Mhz to 70,200 Mhz. So I set my 4m. WSPR in 70,153 (RX). I am Beaming from Madrid to Central Europe and UK. 73, EA4ETR Juan Carlos.

Ok. I swapped out the RK20 kit receiver for my beloved IC703 receiver.

With just a few hours of use its clear its maybe up to 13db more sensitive on the same stations I'd been receiving on the kit receiver for a few days now.

No big surprise in that. Interesting to see the differences in signal strength.

What is unclear is why I'm just hearing the one station. I would have thought that even with the in-office-dipole it would hear a few more distant stations with the better receiver in the IC703. It would seem not to be the case.

For the last few days nearly all I've heard are local stations with a few ZL spots.
Clearly my antenna and Rx combination is sub sub sub-optimal.
Next test is to swap out the Rx for a full commercial Rx and compare.

I spent the last few days experimenting with modifications to WSPR to enable it to transmit at variable power levels. I had the idea when I was playing around with the Tx output level from my SignaLink box. I realized that I could reduce the power output of my WSPR signal from my transceiver by varying the audio drive levels. I guess that's obvious. However, I also realized that I could achieve the same thing if I could vary the amplitude of the generated wave file in the WSPR application.

After a few experiments I discovered that I could modify the fortran code to reduce the wave file amplitudes and achieve a corresponding reduction in output power. One thing I found out in the process was that once the audio levels dropped below a certain point, the VOX capability on the SignaLink failed to trigger the PTT. There is a jumper (JMP4) inside the SignaLink that increases the sensitivity. With that in place I was able to vary the power level down -13dB from the maximum. I could probably achieve a lower drive level if I used CAT control to enable the PTT.

So far I have a version of WSPR compiled on Ubuntu 14.04 that sequences my WSPR transmissions through 20, 17, 13, 10 and 7 dBm. I haven't modified the GUI yet - so any changes have to be compiled into the code.

The key to getting it to work is to measure the power output very accurately (I use an oscilloscope to read voltage) and adjust the SignaLink drive Tx level to give the correct output at the highest power level in the sequence. The modified WSPR software then varies the power over the ranges I have programmed in. It's important to make sure the drive level is below the ALC of the transceiver to ensure that it is accurate. In my case I am using an FT-817 at 500mW nominal output, with the SignaLink driving it to produce 100mw (20dBm) at the maximum power level.

See attached picture.

Recently I changed the stage after
the DDS module into a single 2n2222.

Rx built in an hour. Aligned. Antenna is hookup wire 2 m high run around the office. No gound wire, just DC power cable to the PC. Not tuned. Complete rubbish as an antenna! If I can receive you, you've got a great signal!
Things will only get better.
Goal is to leave it running (with a much better antenna of course).
Not being a transceiver, means it can happily stay working 24/7.

I will be pointing to North America on 6m WSPR.
Schedule is from 20:00z to 24:00z on 27th and 28th of June.
Please give it a try.


Les invito a visitar el sitio

5 to 7 april 2014 - 14 & 21 MHz - Test period with 5 mW (good results),
1 mW (significantly less reports) and 200 µW (no report during a 2 hour test only).
Mostly embedded into RTTY activity. To be continued during quiet periods.

Using vector voltmeter HP8405A for power calibration and a vertical antenna.

Thanks to all WSPRnet contributors and operators from Marc F6EMT