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.

Well pleased, I've finally managed to be heard in Australia. VK1UN on 10MHz SNR -28 dB!

Winter is easing its grip, but it is not yet time for antenna work, so the
anti-parallel dipoles mentioned in the previous post will have to wait.

While the weather is warming up, the 85 watts dissipated by the IC-761
during WSPR-reception is a bit of a waste; soon the shack will need
additional cooling with all equipment running. Therefore a "hundredfold"
reduction in rx-power is very welcome. Presently 15 volts 40 mA is fed
to a 7812 regulator followed by a 7808 to provide 12 and 8 volts bias to
four 8-pin chips, namely a SA612A - NE592 - SA612A - LM318H string.

SA612A mixers have very low bias, so they are prone to overload and
IMD when fed with wide input spectra. In this prototype receiver some
risks are taken, but narrow pre-filtering is expected to minimize the IMD-
problem. Due to the availability of standard crystals for certain frequencies
the 10140.2 kHz band-center seemed within reach with a 4.000 MHz and
a 6.144 MHz crystal. Both had to be pulled down a little off their nominal
frequencies for WSPR action. So we are talking about a superhet.

The first SA612A has the 4 MHz crystal in its oscillator section so
6144 kHz is serving as the intermediate frequency. Actually another
6144 kHz crystal is used as the IF-filter in the NE592 stage between
pins 2/7. It is in fact not a straightforward filter: it kind of "shorts"
two emitters of the NE592 at X-tal series resonance, which peaks
the amplifier gain enormously at around 6140 kHz. Bandwidth is not
much more than the 200 Hz WSPR-band, so it is quite a remarkable
response for a single high-Q component in that particular circuit.

The second SA612A makes a 6144 kHz crystal oscillate round about its
nominal frequency, so both the 4 MHz and 6144 kHz crystal have to be
pulled down with a series coil to arrive at band-center 10140.2 kHz with
1500 Hz BFO offset, actually in LSB mode. As standard WSPR offers

Please ignore my info spots 2011-04-01 07:24
No correct power info. Sorry. Run WSPR in XUbuntu
Now all ok! Good bay Windows :-(((

I am running a stand-alone WSPR beacon with my qrp SDR Cube with no stickin' PC! 1 watt in a G5RV on 40 m

Today I started running WSPR on my HCJB Pappradio SDR-Receiver. It's receiving only. Running on an 22m endfeeded indoor antenna I would see what this little thing can receive in WSPR Mode.

My handle is Basil from the City of Malabon ,Metro Manila ,Philippines

You can visit my qsl information at www.qrz.com/du1br

I use the WSPRnet whenever I need to contact stations who are on the map.

So if I see your call-sign I will not hesitate to contact you 73 and Mabuhay! de Basil

DU1BR

Time for the transmission:

Every day from 20 to 24 h GMT

Dias, frecuencias y modos de transmisión para el Periodo de Actividad en 500 kHz

Activity Period fron 1-4-2011 to 30-4 2011

Día Día de la semana Frecuencia (Dial) Modo Shift a portadora = 1500 Hz

I upgraded to 2E0VKG back in February, but other commitments have meant I've not had chance to get back into WSPR - until now.

Currently QRV on 40m, with 100mW (20dBm) into a long wire about 4 metres above ground. I'm controlling the output power by backing off the input audio, so not the most accurate way of doing things, but the FT-897 will only allow 5W as a minimum TX power.

Things look to be working okay, anyhow, as I've been received by W2OL and W3GXT, both in the US, and LA9JO in Norway.

I am quite excited by the latest WSPR result from my 136 kHz beacon! My 1 W audio amplifier (taken from a cheap PC speaker set) has been heard about 150 km away from my QTH! It happened during the day, so it's straight groundwave propagation. This is a stock standard TDA1517 based amplifier, which only a 4 to 50 Ohm impedance transformer attached to the output of one channel and a fan to keep it cool! The antenna used was about 13 metres of wire, slopping up, with the highest point being about 9 metres off the ground - nothing special in other words.

Who says LF is difficult?!

I am seeing signals on 30 meters that are out of time by as much as 20 seconds. You must be reasonably close to the time interval WSPR uses if you are to hear or be heard. If you can't maintain proper time you are just wasting spectrum and electricity. Dimension 4 is a free download http://www.thinkman.com/dimension4/ which will mange keeping your computer time accurate. There are plenty of posts in the forums on setting it up and about NTP and timing issues.

Sorry folks I have been running with the wrong Locator showing,error pointed out by G3JKF, many thanks Ken for pointing it out.Now Correct at JO03DH

Testing with the IMAX2000

Online 08.03.2011 / 14 - 17 UTC

On 5 FEB 2011 I updated to WSPR2.20_r2283 to frequency hop receiving on 160 through 10 meters but had enabled transmitting only on 7 and 14 MHz where my 40 meter horizontal loop's SWR is under 1.5:1 without need for an antenna tuner.

On 6 MAR 2011 I cautiously enabled transmitting on 10, 12, and 15 meters where the SWR is less than 3:1, expecting no harm to the output transistors running a mere 5 watts. I was pleasantly surprised by spot reports comparable to others on those bands!

Antennas used in WSPR-experiments may have very differing structures. As such I do not think
that there is any specific recommendation. One uses often an existing antenna originally built for
completely a different purpose. Personally I started my HF-career for this particular location
30 years ago with log-yagis (3-element log-cells with a parasitic reflector and director) at various
heights. With WSPR I have used these on the “wrong frequencies”, that is: hardly ever on the
14 - 28 MHz bands those have been designed for. Since I have operated WSPR mainly on 7 MHz
and 10 MHz, the elements of those log-yagis have been electrically “too short”, thus specifically
yielding poor pattern and efficiency in transmit mode. While WSPR is generally not intended for
point-to-point traffic, the described behavior has been actually often more welcome than operation
on the initial design frequency of the antenna. Simulations with horizontally polarized 3-element
off-frequency log-cell structures show best field strength toward the horizon, but not in a controlled
or optimized way. Additional uncertainty about the pattern is introduced through usage of the feed
point matching arrangement on an off-design frequency. A big burden on such an arrangement is the
presence of numerous local sources of man-made interference these days.

So the chase for better SNR is imminent, preferably with a structure that scales well with changing
frequency. Such an antenna cannot be an isotropic, though that would be an ideal antenna for WSPR-
experiments when aiming for a minimum number of variables. Isotropic behavior is a theoretical
concept though, especially when taking into account ground reflection effects. However, anything
of the perfectly round pattern of a free space isotropic that (by changing radiator layout) can
be shaved off from specific azimuths or elevations, can be steered to add increased gain toward

MY CALL SIGN HAS BEEN CHANGED FROM AK5U TO N5LJT.

I WILL APPRECIATE HELP IN CORRECTING THE CALLSIGN ON MY PROFILE PAGE HERE.

THANKS AND 73, FRED N5LJT

I ran WSPR nonstop for a week (RX only) using the internal sound card of a Giada N3 Atom computer, and then switched to a 24-bit external sound card for another week of nonstop spotting. The results with the internal card were a worse, which is not surprising, but not by much. Click here for more details.

Not connected to internet where my rig is. Just decoded KC6KGE at 0752 UTC
db= -26, dT -1.3, Drift 0, Loc DM05 my Loc QE36.
73 de VK7HW

August sometime - to be confirmed. 2009 : Pencarrow at the mouth of Wellington Harbour - good fun was had, with a fullwave 160m dipole from the upper lighthouse all the way to sea level (the bottom end was IN the surf at high tide!) but the digital modes didn't get a chance due to interference caused.

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