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.

As I had to update my Tom Tom navigation on the internet I had some time left at the same time to
install WSPR. At first I had some problems to get the RX noise level at 0dB as the built in RX/TX volume controls
do not work here in Vista. I had to adjust the volume at my modem. Then I was surprised and impressed that with only 1W I was received in India at 30m. This is really worth more investigation.
My blog:

For this activity period, I left the receiver on the 80m frequency from the afternoon of the 22nd to about 08:00 utc on the 23rd.
Antenna : A very low dipole only 4-5 metres above ground level.

As expected, lots of EU stations. Most running several watts so nothing special. 2 exceptions were G3NFP running 100mW (~440 kms) and G0VAX running 20mw (~390 kms).

To the East, VK6POP (10w) was heard twice which was a big suprise! This was about 90 minutes before my local sunset (20:38 utc)

80 metres SAD overnight was good - several European stations, one at 0.1 watts.

The azimuth provided on the database for the European stations looks odd to me.

the map shows Short Path (which should be the default I guess), however the database show different.

for example:
Timestamp Call MHz SNR Drift Grid Pwr Reporter RGrid km az
22:40 G3WPD 3.594072 -24 0 IO91qq 10 VK6POP OF88bd 14525 92

W5OLF, 1901 km away, received my 0dBm (1 mw) signal. I am truly impressed with what WSPR is capable of.

M1PAC here
I have joined the WSPRnet
yet to link it up tho the T/RX
but will be looking forward to using this

Having fun with WSPR - I'm in an apartment with antenna restrictions - so I'm using an AEA Isoloop 1 meter diameter loop on 30m and 20m
The rig is a Yaesu FT 817 running 5 watts - The Computer is an Apple Mac PowerBook Laptop running WSPR inside Windows XP Pro inside the Mac Parallels virtual machine!
Works quite well.
Guess next is to try JT65 to make a two way contact...

What is an alligator? In radio terms it's a person who is all mouth and no ears. If we apply the same idea to radio stations (not people), do we have alligators on WSPR?

On a typical overnight (midnight to 8am my time UTC+8) session on 40 metres, I will hear around 6 Europeans and a small handful of North Americans. Yet most nights I am only heard by a small few of those stations.

What does it say about a station's Rx capability (including environmental issues)? Where are the principles of reciprocity when I hear a 0.5 watt signal from 14,000 km away and my 10 watts is not heard in return?

The reciprocal principle says that, all being equal, two stations should hear each other the same, however it's clear to me that all isn't equal.

It's not sour grapes driving me to write this. I just wonder why a station with a Tx antenna good enough to make a 0.5 watt 14,000 km trip, can't receive a signal much greater in magnitude over the same distance/path. Are the paths really one-way so often?

I think I'll take an aspirin and lie down for a while - too much thinking :)


Vacation time - radio time, right ?
The very same day my summer vacation started, which I usually spend at the summer/ weekend QTH, 30 km SE Stockholm, I started to check out this "WSPR thing".
A friend of mine, SM0IKR Goran, had been whispering about this incredible, impressive digital mode.
I´ve been into some digital modes already, but I had heard Gorans voice in my head, for the last weeks, over and over again: "...running just a watt or two... with VK... .working the world..."
So, now I had time, so let´s check it out.

And now I´m stuck.

The software is really impressive, not talking about the result itself. Until now, I´ve roughly two days of experience of WSPR.
Amazing mode.
The rig here at the summer/weekend QTH is a FT-897, and a number of wireantennas hanging around in the pine trees.
The house is in a forest area in the archipelago of Stockholm, so antenna support is directly available.
With the pine trees surrounding the house, some vertical 1/4 wireantennas have seen the light, and today, I got a new 7 MHz 1/4 wave wire vertical with two radials up in the sky.
The 10 MHz antenna is also a vertical 1/4 wave with two radials.

I left the rig on 40m for most of the activity period running from early on the 15th to around 08:00 on the 16th.

Using a very low doublet (~5m agl), the following were heard :
Europe....usual stations although DL6NL with 50mW was weak but consistent for the whole day.

DX...the following were logged :
VE3ODZ (5w)
WB4KLJ (2w)
KE7A (5w) in Texas...consistent signal for ~4-5 hours both mornings.
PY8ELO (20w)

I'm quite new to this WSPR hobby and I'm playing with quite moderate toys: IC-718 + Windom. I'm still only listening, but hopefully I'm soon sending also. My first interesting finding in the log was found last night: PY8ELO was heard on 40 meters. Not bad.

Just got going as a receive only station. Took a while to figure out where the correct 200 Hz band was on 30m ;o)

My current receive set-up is very modest. Rig is a Kenwood TS690s. Antenna is a doublet antenna.....which is basically a 40 and 80 metre dipole in a fan arrangement and fed with 300 ohm twin cable. Height is very low.....only about 4 to 5 metres high.

090701 0124 23 -8 1.2 10.140194 K5XL EM12 30 0 1 0
090701 0126 23 -9 1.1 10.140194 K5XL EM12 30 0 1 0
090701 0128 14 -18 1.4 10.140168 WB3ANQ FM19 30 0 1 0
090701 0128 24 -8 2.5 10.140242 K3SIW EN52 30 0 1 0

090701 0128 5 -26 2.5 10.140251 5H1/4A1LSM R S8 -4 11664 -36

I have designed and built a versatile WSPR beacon that works on 160m to 6m with up to 15W.
It derives time and location information from a GPS mouse and creates WSPR data locally without the need of a PC.
It has a LPF switch module and a attenuator switch module. It can run multiple DDS/PA modules concurrently.
Initial config is done with a Windows utility over USB. Details on the project are available at

Have a look. I would be happy about comments

73, Gernot, OE1IFM

26 june 2009: I've made some mistakes setting right power in WSPR. All the day it was 2,5W

The results from my Home Brew DDS Multimode test on 28MHz using 300mW have been truly amazing. The time has come for it to be switched off shortly. Many thanks for all those who looked just below the WSPR band for my signal and particularly for the Visual Mode Screen Grabs.

Next test in the future may be with approximately 50mW as 28MHz opens up.