Well, youv’e gotta do a test or two, youv’e……………..

The XORgan went for a short recital on HF today running 1 Watt first 0n 40m then 30m.

Right Click on the pic. and select View Image for full size.

People on WSPR thank the RX stations on the Chat page, OK, well, thanks to following stations but then you had no choice did you.

2009-10-31 12:40 G3ZJO 10.140191 -17 0 IO92ng 0.05 DL0NOT JO40jf 709 105
2009-10-31 12:40 G3ZJO 10.140181 -18 0 IO92ng 0.05 OH2MZA KP01ro 1692 44
2009-10-31 12:40 G3ZJO 10.140185 -18 0 IO92ng 0.05 DF2LV JO44rs 737 64
2009-10-31 12:40 G3ZJO 10.140186 -1 0 IO92ng 0.05 DL2NI JN48ul 860 115
2009-10-31 12:40 G3ZJO 10.140193 -10 0 IO92ng 0.05 OESWL JN67qu 1127 110
2009-10-31 12:40 G3ZJO 10.140207 -6 0 IO92ng 0.05 DL4SR JN49wc 834 111
2009-10-31 12:40 G3ZJO 10.140185 -23 0 IO92ng 0.05 W3CSW FM19kd 5811 288
2009-10-31 12:30 G3ZJO 10.140189 -22 0 IO92ng 0.05 W2WH FN30kr 5437 287
2009-10-31 12:30 G3ZJO 10.140183 -15 0 IO92ng 0.05 DF2LV JO44rs 737 64
2009-10-31 12:30 G3ZJO 10.140221 -4 0 IO92ng 0.05 PA0BWL JO21ss 442 95
2009-10-31 12:30 G3ZJO 10.140186 -4 0 IO92ng 0.05 DL2NI JN48ul 860 115
2009-10-31 12:30 G3ZJO 10.140207 +4 0 IO92ng 0.05 DL4SR JN49wc 834 111
2009-10-31 12:20 G3ZJO 10.140207 +4 0 IO92ng 0.05 DL4SR JN49wc 834 111
2009-10-31 12:20 G3ZJO 10.140186 -19 0 IO92ng 0.05 K1JT FN20qi 5561 287
2009-10-31 12:20 G3ZJO 10.140186 -4 0 IO92ng 0.05 DL2NI JN48ul 860 115
2009-10-31 12:00 G3ZJO 7.040097 -11 0 IO92ng 0.05 G6PHT IO92of 7 129
2009-10-31 12:00 G3ZJO 7.040079 +3 0 IO92ng 0.05 GM3RXU IO86qg 459 346
2009-10-31 12:00 G3ZJO 7.040125 -8 0 IO92ng 0.05 ON7KO JO21ce 370 107
2009-10-31 12:00 G3ZJO 7.040096 -21 0 IO92ng 0.05 LA9JO JP99gb 2124 21
2009-10-31 11:50 G3ZJO 7.040079 -1 0 IO92ng 0.05 GM3RXU IO86qg 459 346
2009-10-31 11:50 G3ZJO 7.040126 -4 0 IO92ng 0.05 ON7KO JO21ce 370 107
2009-10-31 11:50 G3ZJO 7.040096 -16 0 IO92ng 0.05 LA9JO JP99gb 2124 21
2009-10-31 11:40 G3ZJO 7.040095 -17 0 IO92ng 0.05 EI9FV IO63vk 381 292
2009-10-31 11:40 G3ZJO 7.040096 -14 0 IO92ng 0.05 LA9JO JP99gb 2124 21
2009-10-31 11:40 G3ZJO 7.040098 -9 0 IO92ng 0.05 G6PHT IO92of 7 129
2009-10-31 11:40 G3ZJO 7.040148 -26 0 IO92ng 0.05 G6PHT IO92of 7 129
2009-10-31 11:40 G3ZJO 7.040080 +3 0 IO92ng 0.05 GM3RXU IO86qg 459 346

Tests on 2 bands over and done in 1 Hour, glad I didn’t stay on longer, its was pain re tabulating that lot.

And finally a neater version with PIC Modulator on test.

Generation of WSPR using XOR Gates

I am contemplating calling this the XORgan.

I realise that this blog is the one that links from my web site. My other blog with more information on the WSPR Organ can be linked to from here.

On Sunday 25th of October I had an idea for generation of WSPR signals in a very simple KISS method using 2 Crystals and an XOR 74HC86 Mixer. By Sunday evening it was built.

It works really well, by the use of two identical Crystals and subtractive mixing any drift in those Crystals is cancelled resulting in an extremely stable Audio data stream.

A vast range of Crystal frequencies could be chosen I am using 10.0005MHz at this time, I wondered if this may be a problem for 10MHz reception but the frequency is far enough away from the Amateur allocation to cause no trouble. I have also used 8.192MHz.

The circuit shown is liable to be modified I didn’t bother with an LPF after the mixer, the capacitor values were sufficient but I may try an RC LPF in there or after the Buffer. As the circuit stands the output is a very clean Sine Wave.


I have added an RC Audio LPF at the output during test, it cleans the sine wave of any miss shaping nicely.

The LED shown used as a Varicap is sketched upside down for me, I always use them reverse biassed, some use them forward biassed, in this way positive or negative keying can be utilised.

WSPR Organ – XORgan – PC Less WSPR TX

The ability to ‘go anywhere’ with an MEPT is increasingly more desirable, unless you want to sit ‘Rock Bound’ on 30m or use DDS.

Many of us have a Multiband TX/RX which can run QRP but for some modes, (WSPR), a computer is needed in TX only mode which makes a mockery of the term QRP as applied to Station power consumption.

We have produced PIC based MEPT’s for Multi Modes and WSPR.

Some have recorded WSPR audio on MP3 and re played that for Computer-less operation.

I think Computerless is a well understood term in all walks of life. Well this uses a lot less Computer than most. This uses a small PIC processor with no external memory, sound card, hard drive, video card, monitor, keyboard or mouse and I swear it has never had relations with Microsoft, or Monica Lewinsky.
For the purists I shall say PC Less in future, if I remember.

I have now produced the KISS WSPR Organ. Sorry Whisper refusenik’s for the name, it does QRSS just fine.

The name stems from my original idea of using a musical tone generator to produce the WSPR tone frequencies. Talking to an Organ engineer yesterday morning soon proved that approach to be far too complex and my simpler KISS idea was implemented.

The Output can be applied to any HF/VHF SSB Transceiver or better, a simple home brew SSB TX.
The PIC will provide QRSS Morse, Hell, Patterns, WSPR whatever, plus PTT TX/RX switching for any pre determined periods
There is an advantage over the ‘generate on frequency’ MEPT in that nothing is running on signal frequency so the generator can be left running during receive periods.

Two Xtals on the ‘same’ frequency use a single 74HC86 for Oscillator, Mixer and Buffer. One Xtal is pulled 1.5KHz HF and the PIC modulates this Oscillator also.The modulated 1.5KHz signal from the Mixer is selected, fed to the Buffer and feeds the TX Data Audio Input via a Set Level pot.

Just one chip and that’s it. And it works, this from G6AVK at 127Km on 50MHz.

And on WSPR it is performing well no drifts in some 10Hours use, again thanks to G6AVK for the reports. The severe Aircraft Scatter has caused a bad decode but we are used to that on the direct path.

Sorry the power level shown is erroneous due to the experimental nature of the project, on 6m this is less important than on HF for any database information. The level stated when accurate is actual Power into 50 Ohms at the Antenna Socket not ERP. The use of beam antennas make any ERP estimate impossible (was the RX station on the side or back of the beam).

The input will be from your favourite PIC modulator with suitable level adjustment and shaping. The LED I show used as a Varicap can be either way up depending upon your normal methods. I use it reverse biassed, the opposite of how its drawn:-)

I added an RC Audio LPF to the output and a divider and pot for easy deviation level setting.

6 Meter si 570 Sythesiser MEPT

I use my blog as a reference for myself. Today I looked for a picture and description of my 6m si570 MEPT test set up here and found I mentioned it but posted nothing.

To save confusion I have removed the term DDS althogh they are generally getting called DDS now which isn’t strictly correct.

So here we go.

Here we see the s1570, SL612 Mixer, 16F628PIC Modulator, 2n3866 equiv PA.

In total 8 active devices 5 IC’s and 3 Transistors for 100mWatts of WSPR on 50MHz

Oops I’ve done it Again

I think I can say I have the drop of Aircraft Scatter now. I noted straight WSPR reflections which de-coded from the North, with the aid of G6AVK I was able to predict the flight path of the reflecting Planes.
Next G6AVK and I beamed SE to the Thames Approach and achieved some straight de-code-able reflections of WSPR.

In the next step I calculated possible Airline routes that could produce straight reflections for our two stations, G6AVK and G3ZJO, the calculations are only valid for these or similarly located stations. A test this week of one route produced some near reflections but nothing that de-coded.

Today I asked G6AVK to beam to Fishguard as per my map.

Within 45 minutes we struck lucky with a plane on the right track and the following de-code.

Only the reflected signal de-coded, the direct path being corrupted by local A/S. The Doppler shift shows only 24Hz which equates to an Aircraft Speed of only 257.68KmH Yet something else to think about.

The Spectran Grab shows some tangential variation which could well corrupt the calculations.

WSPR fun in the Orionids Meteor Shower

Wednesday the 21st of October saw the Peak of the Orionids Meteor Shower coinciding with a 6m activity day on WSPR.

I could have been on JT6M looking for M/S activity or joining in the E/S opening to Spain, however I decided to beam East with WSPR. G3XBM near Cambridge was on, after some overhead A/S was observed I captured an interesting one.

Now all we need to do is explain the signal which defies all the rules for Aircraft Scatter. What I think we are seeing is a meteor shower relatively overhead of G3XBM this has caused E layer reflections for some 15 seconds followed by some fast moving trails for another 15 secs. at the end of the period some fast moving patches of ionisation (from break up of a Meteor?) cause reflections that I think resemble smoke rings.

If you have lots of knowledge of extended period reflections from meteors it would be great to hear your interpretation.

The Sporadic E from the meteor shower lasted for some time, this later Grab is easier to explain.

I turned my beam to the North East, knowing that SM6NZV and OZ1PIF were operational.

2009-10-21 07:58 SM6NZV 50.294406 -26 0 JO57xk 5 OZ1PIF JO65an 209 179

The trace is at the correct frequency for SM6NZV and the WSPR signal is visible for the complete 2 Minute period via Sporadic E from the Meteors, at least 5 meteor pings are clearly visible and were audible. Unfortunately the signal did not de-code.

Yet more Aircraft Scatter Experiments on 6m

Some of the activity here at the weekend was devoted to attempting to get some signal by any means to SWLGM Mark in Edinburgh. Very little signal was seen from either G6AVK or G3ZJO on Marks 6m Zepp antenna.

The use of WSPR gave the chance to look for Aircraft Reflections which produce a double de-coded report. There were several examples spotted and screen grabs taken of them. I am still not certain of the distance involved to the reflecting plane. Currently I think it is quite large c.500kM.

A most interesting de-code came late in the day. A double de-code of my signal at G6AVK.

This shows only 1dB less signal strength for the reflection compared to the ‘direct’ path and a 51Hz shift.
Luckily G6AVK also captured the WSPR Waterfall and better still a Spectrum display.

The top trace is the Direct Path signal, 51Hz below is the Reflection which de-coded, clearly many dB lower than the Direct.
Between these two is a curving reflection, stronger than the direct signal, this type of signal has never been seen here to decode the WSPR data.
After some thought I can offer an explanation of the mechanism involved. I am quite happy to listen to alternatives.

The trace 51Hz below the top direct path one produced the de-code, it came from an Aircraft flying North in the North UK Air Lane.
The curving trace comes from a much closer (to G6AVK) Aircraft, joining the South South East Air Lane (off to the South of France) and reaching a cruising speed very close to that of the Aircraft travelling North. Using standard speeds in a control area is the way that Aircraft are kept apart. Reaching the right place at the right time is a game of chance, we had been playing roulette all day.
So is the alignment of G3ZJO G6AVK and The SSE Air Corridor a possibility, yes this is only a rough layout on the map.

Right click and select View Image for full size.

So finally why the odd report of a strong signal level from WSPR. I believe that the signal from the closer Aircraft to the south swamped or reinforced the complete reflection, the decoder giving an average strength reading over the whole period. Joe?