Several new features are included. At last we can use /P when we are out Portable and a proper prefix in a foreign country i.e. F/G3ZJO, and a full 6 figure QRA Locator. This has been a constant source of embarrassment for me, sitting on a Ski slope in France using my Home Call and two thirds of a Locator which was exactly the same as when I was in a town several Km away at the foot of the Mountain Range.

In addition there is a version for Linux. I can see a huge expansion now in the use of Linux, particularly Ubuntu in the Ham Shack.
Well done Joe and the Team.

Comments

A 13.5MHz Crystal Oscillator is configured as a VXO this is subtracted from a 14.0MHz Modulated Crystal Oscillator to produce 500KHz. This goes via an LPF to an Inverter PA, on the underside of the board, which produces 150mW of RF via a further LPF.

The Output signal is very Pure and Stable. Frequency stability can be seen from the following decodes in a 5 hour period.

091113 1050 13 -17 -0.1 0.503923 G3ZJO IO92 17 0 1 0
091113 1250 14 -18 0.8 0.503923 G3ZJO IO92 17 0 1 0
091113 1520 14 -18 1.8 0.503923 G3ZJO IO92 17 0 1 0

Comments

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.

Comments

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.

Comments

I thought I had better put the DDS in brackets 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

Comments

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.

Comments

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.

Comments

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 come 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 signal level from WSPR. I believe that the signal from the closer Aircraft to the south swamped or reinforced the complete reflection, the de-coder giving an average strength reading over the whole period. Joe?

Comments

The above 'curtains' were short lived. The 100Hz spaced carriers persevered for a few days.

This managed to convince me for a time that the 25Hz bands were harmonics of the 100Hz ones, when the QRM varied the 100Hz carrier were contiguous. Yes sure they are all sync'd to the 50Hz Mains supply so they would be.

Today the 100Hz carriers had gone, both here and in the Shetlands, at 07.09 UTC the 25Hz carriers started. I decide to take a rest from house maintenance and do some Direction Finding.

At 08.16 UTC I asked a neighbour "would you switch your TV off please".

It was a December last year purchase, hence the QRM I had seen on 80m, a Panasonic Plasma TV model TH-42 PX80B. Fairly new neighbours who I have not had the chance to chat to and say if you buy a new TV don't ever buy Plasma will you. I just hope the product life is very very short.
Just like the Home Plug PLC fiasco modern products do not meet the standards needed to prevent interference on the Short Wave bands. Ofcom the people who should enforce the standards are a feeble pawn of the Government and money talks.

Comments

I was pleased to achieve 890Km with 1mW myself, but even more pleased to receive other stations who are running that power level. At this QTH I have high noise levels and a regular almost constant comb of 4 or 5 carriers spaced at 25Hz.

I don't think it is local, i.e. TV's or computers, it seems to come and go with propagation. It threw me the other night when just after 23.00 it went off abruptly. Maybe a TV then. However note the 10 minute break in the screen grab above, then change of format, not consistent with TV or computer use.

This is what the carriers look like on Spectran.

Comments

The capture below shows my signal at the bottom, the strongest trace, and the locally generated one above with details as reported as Spots.

Comparison is not that easy due to size difference but conclusive, OK2SAM is transmitting a double width signal. It will be interesting to find out if it is indeed a home brew WSPR set up he is running. The Locator is a Portable location, and he does not seem to receive any stations.

Finally to aid identification I have separated individual lines of data for comparison, the middle lines suffer from noise, the best one to illustrate is the bottom line. Sized to roughly the same dimensions.

I am now in communication with Michael OK2SAM, he is running a most interesting home built 3 band WSPR beacon, I am sure he will find out the cause of the problem soon now he knows about it.

Comments

At first DL6NL and I thought it could be a new home brew WSPR TX not yet adjusted correctly. I checked the exact width of the signal and found it to be exactly double the correct deviation. Unlikely I think that someone capable of producing his own system would adjust to precisely double.

One way to achieve this would be to use a system which used a doubler on the correct WSPR signal to reach the desired transmit frequency.
F6IRF has recently seen the signal again, it seems to be the same signature, the mystery deepens, does this operator know what he is doing, surely he has never had a decode.

Comments

Today an accidental alignment of beams at G6AVK and G3ZJO has produced AS which approaches the path between the two stations then vanishes. I surmise that these are reflections from Aircraft on the Thames Estuary approach from Europe which may well vanish when past the front of the AVK beam.

Looking at the capture at 13.30 GMT there is a straight line AS reflection which decoded, it has a 53Hz shift but this time positive Doppler. This is the first time positive straight line Doppler shift has been observed here. Again I assume from an Aircraft on the EU Thames approach heading toward G6AVK and G3ZJO at 53x540/50.294436 = 569KmH

Comments

Always extra pleasing is a capture or three of the Visual modes.

First in was Paolo IZ1KXQ in Italy.

Next up a capture of the WSPR display but from France F6GUU a Country we don't see many reports from.

Edit : And another from Pat F6IRF in JN35AU on the 7th of June.

Third Spain from David EA1FAQ.

The MEPT is running 300mW, the Antenna is a 6m CB type Vertical at ground level. I knew 10m was going to be good fun. this is the first time I have run a QRP MEPT on the band.

A great quote from an Alaska station today, "its so exciting I may not be able to hold my water". I know just how he feels.

Comments

Here is just one Plane of the constant stream which passed my QTH and my 6m Vertical Dipole today.

Right Click and select View Image for full view.

It would be interesting to find the true distance at which this one passed, I estimate 1 Mile. I think Aircraft in the Corridor can be anything from Overhead to 20 Miles away.

Comments

The Aircraft needs to be, I believe on the same bearing as that of the path between the two stations.

At my QTH this is merely a waiting game, there are so many aircraft on the S/N corridor that finally one will fit the equation.

Previous tests with G6AVK did not achieve the desired result. I think that, while his omni directional signal reached me fine, by the time it got to Aircraft sufficiently North of me it had run out of 'steam'.
The addition at G6AVK of a mast and rotatable 6m Beam means that strong Aircraft reflections from the North are now possible.

I pointed my beam in line with the S/N UK Air Corridor G6AVK beamed toward me.
Note the trace at 19.32. There is the direct signal from AVK. A long descending trace from an Aircraft, which has passed me and is heading North, on a track at a tangent to the path between AVK and ZJO. Third a parallel trace, ‘classic’ 61Hz shift equating to an air speed of c.600Km Hour.

This produced 2 decodes of WSPR on the two frequencies.

2009-05-29 19:32 G6AVK 50.294482 -18 1 JO01ho 5 G3ZJO IO92ng 127 306
2009-05-29 19:32 G6AVK 50.294421 -25 0 JO01ho 5 G3ZJO IO92ng 127 306

I think we can now say that this is the definitive explanation of the phenomena. Repeatable by experiment, using 3 different signal sources.

Comments

Right Click on image and select View Image to see full size.

The grab above shows a straight line signal 59Hz below the original signal which itself appears to be effected by AS.
This lead to G8EUX testing his TX for spurious emissions and me saying it cannot be an RX odd response due to the fact that the second signal has AS. To add to my identification as a Scattered signal I never see odd decodes from G8EUX even when signals are much stronger.

After some thought I came up with an explanation.
The straight line is AS and the other related curve is from another aircraft reflecting the fundamental signal. Being a straight line reflection means the Aircraft is moving away from both stations on a constant path relative to both stations. The Doppler shift of 59Hz thereby gives us the Aircraft speed. Which works out at 633KmHr.

One example of this phenomenon does not prove anything so I began to consider a method of proof.
Beacon GB3BAA on 50MHz lies to the South East of me, not parallel to the Controlled UK Airspace South North routes but knowing the flight paths I decided to give it a try.
Pointing my beam North away from GB3BAA I set Spectran so that the beacon was just at the top of the display, only the Morse Ident Keying, lower sidebands can be seen.
I was most interested in the minus 50 to 60Hz Doppler shift region. In a short time an example of 60Hz straight line shift occurred. There are short periods of no AS then just like buses several come at once and many with a straight line portion with a Doppler shift of 50 to 70Hz.

Right Click on image and select View Image to see full size.

So what are we seeing? One explanation I can put forward is.
As the AS signal descends in frequency we are witnessing Aircraft travelling North away from both GB3BAA and G3ZJO and at an angle having already crossed the direct line signal path. As the Aircraft turn to cross the Atlantic there is a period when the trigonometry produces the straight line. I do not show the signal path from GB3BAA to G3ZJO. Its not critical, just think of GB3BAA as being down London way.

Right Click on image and select View Image to see full size.

Equally we could suspect that the Aircraft involved could be turning earlier to take the route across via Ireland, there is an example in the animated plot doing just this, I consider the angle to be too large for this to be the case.

Comments

Right click and select View Image for full view.

Compared to the 74HC240 PA version total efficiency is low, only 12.5%. Total consumption including si570 being 4Watts, not my idea of true QRP but once you throw that Xtal away you are on a slippery slope. I quake in fear at some of the temperatures that silicon gets run at so I added a 'Smoke Stack' to the output transistor heat sink. Here is another view.

To the right of the 'Smoke Stack' is the band specific LPF at the left hand side is the band specific input filter. Both modules are easily changed over, just 3 solder links on each for band swapping.
Here we see the si570 Synthesizer, mixer and PIC WSPR, Hell and QRSS modulator.

I have run on air tests on 24MHz and 28MHz, unfortunately with no reports as yet. Future band improvements should change that soon.

Comments

Previous tests using 100mW of Slowfeld produced very useful copy at G6AVK of G3ZJO both from the direct beam heading and indirectly by beaming across the North South Air Corridor. The same beam headings were used for the 2 May tests.

G3ZJO also ran a 3 band co-linear antenna for a short time this produced the occasional burst of Aircraft Scatter at G6AVK. Peter, G8EUX produced a little WSPR and me, G3ZJO produced a short bit of QRSS.

G3ZJO could produce constant signals on the Grabber at G6AVK with 100mW to the 5ele Beam,(ERP nearer to 1Watt, I will quote RF out at the TX across 50 Ohms)constant but rarely usable due to multipath.

The most copyable signal that I observed in the test period was the Hell Ident in the following capture. 5 Unit Hell G 3 Z J swoops downward with Doppler shift from an Aircraft reflection and the O is back 'on the line'.

Several versions of QRSS Morse and WSPR proved useless under these conditions, 5 Unit Hellschriber produced some results. Previous activity on 6m by many stations has proved to be disappointing due to multipath signals. The results using Slowfeld which was produced to exploit Aircraft Scatter provided superb communications.

Comments

My Sammy has behaved faultlessly at home, used to provide coding and decoding of Digital Signals in my Amateur Radio station even when running quite high power levels.

I have not seen this problem on any Laptop Computers before. Due to the very low RF field involved it could explain any touch Pad freeze ups when Sammies are used in certain locations and with external leads.

Comments

My previous posts show the hopeless signals on QRSS and WSPR over the 50MHz path between here and G6AVK.
Quite typical of WSPR on 6m the signals are there but the scatter is so great that decodes are rare. My thoughts turned back to Slowfeld.

What you need is that capable Ham at the other end of the path, none better than G6AVK, I put forward the idea ready for his return from a hard day at work (with overtime). While his dinner cooked the software was installed and the tests commenced.

My first transmission produced readable Hellschriber at his end.

Next I took a TX session from him.

Finally I watched my signal on the G6AVK Grabber and turned the beam so that only signals scattered from aircraft were arriving, the TX power was only mWatts.

The results are astounding when QRSS3 FSCW fails and also WSPR then good old Hell comes to the fore.

Many thanks are due to G3PTT for the software which I have tried for several years to put to use. A superb mix of modern computer methods of signal analysis and an ancient visual data mode.

Comments

This time using a 27MHz Xtal, a triple tuned filter and conventional Class A amplifiers the output is 100mW.
On its first on air test signals were received by G6AVK at 179Km. The path crosses the London Luton, London Stanstead and London Heathrow air corridors so reflections were many and sometimes quite bizarre.

The use of Class A amplifiers puts up the current consumption degrading its status as true QRP, maybe I can brew tea with the wasted power.

Comments

All in all it was a successful trial. The complete station including Sammy ran on Solar Power. The Wind was not really significant in the provision of Current.

Running less than 1 Watt of WSPR on 10MHz, (I couldn't run any more power due to the RF problem), I was pleased to be copied in China.

Hiding round the side of the 'van proved to avoid a little of the RF getting at the Sammy.

Comments

ABOVE The Softrock si570 Synthesizer (DDS) Module.

It is not possible to FSK the Softrock si570 oscillator without a computer connected, no good for me, the computer consumption will far outstrip that of the transmitter.
What it does do is generate any frequency up to 260MHz in 1Hz steps without the computer connected. The computer is used merely to set the frequency via USB it is then disconnected.

I am pretty bored with plain old QRSS FSK Morse anyway, so often it is impossible to identify ones own MEPT in the presence of QSB on a grabber despite it being on the correct frequency, no wonder reports do not come flooding in.
Far more identifiable is a simple unique ident or a whole load of different modes which no one else is duplicating and the addition of a burst of WSPR ident every so often.

ABOVE The Modular KISS DDS on 28.300MHz.

The solution to applying modulation is to modulate the Oscillator of a Mixer, I used the SA612. In this way the setting up of the deviation for accurate WSPR steps is done only once.

ABOVE The SA612 Mixer/Modulator Module.

Just one Mixer/Modulator Module is used to cover 1.8MHz to 144Mhz with a c. 9MHz IF Frequency. Any old Xtal frequency will do in the range as the Output Frequency is merely I.F. Frequency + DDS Frequency. For 1.8 and 3.5 MHz it is - DDS due to the lower frequency limits of the si570. 7.0 and 10 MHz would benefit from a 3-4 MHz XTal, VHF could use 33MHz the Crystal is plug in and so fully flexible.
I have tested the Mixer over the full 1.8MHz to 144MHz range, only the 28MHz HiQ Filter/Preamp has been constructed as I write.

ABOVE The HiQ Filter/Preamp Module for 28MHz.

One HiQ Filter/Preamp Module will be required per band. The transistors in the Preamp stage are so cheap they may as well be duplicated for each band. Thus for VHF bands higher frequency devices can be used.

Regarding the Power Amplifier. A Broad Band PA could be used, this would require a BPF for each band and some form of switching. Just like the Preamp the devices are so cheap that including the PA device on the BPF Module is a reasonable choice thus avoiding any changeover other than plugging in the Module.

ABOVE PA/BPF Module 28MHz.

Spot the PA device, it is so small, a surface mount 74HC240 for 50mW Output into 50 Ohms, you can't tell it is there. It is the same arrangement that I have run on 10MHz 24/7 for a year.

ABOVE The precision timed PIC Modulator Module.

This Module produces 5 WSPR based frequency shifts c. 1.4Hz steps to produce any modulation mode that can be achieved with 5 units. I still like this system as the 5th unit is 'free' produced by a simple little trick I used. The De-Multiplexer Enable puts the 4 outputs into an all high state, another set level pot gives me another bit (unit) of information to play with.

ABOVE The Modules connected together on test on 28MHz.

This system allows me to experiment with any individual module and try new ideas for an on going MEPT project for all bands up to 2m. Modules will slide into a standard slotted plastic box for use as an MEPT for a particular band.
There are no plans for a posh enclosure, that would put a halt on its experimental status.
No Digital read out, that would use current that donates nothing to the signal. The 'compromise' of using a stand alone DDS has meant more than a doubling of the MEPT power consumption
No switches and knobs etc. Modules are connected together as needed. Now where can I get some nice little sockets to fit the square gold pins I use on the boards, I have run out.

Comments

On VHF above 6 meters there are a couple of problems, any Rig may be easily be 500HZ off calibration and there still does not seem to be an established dial frequency for WSPR mode.

WSPR incidentally according to our wonderful national magazine Rad Comm which arrived today, 20th March 2009 is a 'brand new mode', 'rather difficult to get going' and 'not capable of any QSO mode communication'. I know it takes time for articles to get published but I am sure glad I don't rely on our National Society to keep me abreast of the latest in Ham Radio.

Anyway, back to frequencies. I carefully calibrated 2 rigs against GB3VHF and G8EUX calibrated his with a 'posh' bit of test gear. We were then both pleased when our RX'd signals reported 2 to 5Hz difference.
The French stations tend to use a dial frequency of 144.48800, a table on the web says 144.48850 after a short period of operation the concensus of opinion settled on 144.48860, there are other frequencies published too.

We had better get these frequencies settled if we don't there will an awful lot of wasted time and effort.

We still need to fix and confirm dial frequencies for 23cm and 70cm.
At this time the frequencies in use are:-

Band Dial freq USB (MHz) Tx freq (MHz)

160m 1.836600 .......... 1.838000 - 1.838200

80m 3.592600 ........... 3.594000 - 3.594200

60m 5.287200 ........... 5.288600 - 5.288800

40m 7.038600 ........... 7.040000 - 7.040200

30m 10.138700 ......... 10.140100 - 10.140300

20m 14.095600 ......... 14.097000 - 14.097200

17m 18.104600 ......... 18.106000 - 18.106200

15m 21.094600 ......... 21.096000 - 21.096200

12m 24.924600 ......... 24.926000 - 24.926200

10m 28.124600 ......... 28.126000 - 28.126200

6m 50.293000 ......... 50.294400 - 50.294600

2m 144.48860 ........ 144.490000 - 144.491000

Comments

When it started to play up I was on air, I saw 10 Amp or more pulses of current indicated on the Ammeter. I was operating on PSK31 with a friend. When I mentioned it he said 'does that not worry you it could damage your rig'.
No, no worries here, this was the practical demonstration of one more reason for the system of 12 Volt supply I use in the shack. The PSU float charges two 40 Amp Hour Lead Acid Batteries individually via Schottky Diode isolators. A fault like this did not apply 15 to 17 Volts to my expensive radios, it might just do the batteries a little good by giving then a few de-sulphating pulses.

'Surely' he said 'your power supply is protected against Over Voltage'.
Yes it is, and Over Current, but this fault was obviosly not related to over voltage, the voltage involved must be a 'legal' one. Any voltage between 0 and 15 is 'legal' it being a variable voltage supply with a front panel adjustment pot.
This should have been a good clue to the cause of the problem, I didnt find it instantly, adjusting the voltage set pot and wriggling it made no difference to the pulses of extra current so I ruled it out at first. Finally I substituted a large preset pot and the problem was cured. I suspect that the connection of the earthy end of the potentiometer track was intermittent possibly under the riveted tag.
I ordered three 10K Ohm pots from different sources and one turned out to be very similar physically to the original.

The original has an indent at the center 13.8 Volt point, the replacement does not. No problem I don't use that point anyway, remember the Shottky Diodes, their foward volt drop means I set the output above 13.80. The original also has a splined shaft the new one is plain so I provided a different ponter knob.

Whilst inside I soldered the wire wrap connections on the control PCB.

Also the wire wrap connections to the load share resistors, these connections do get warm, I am much happier to see some solder on these after several years of use and possible corrosion of contact.
The Regulator Transistor connections on these boards had also had many hot /cold cycles so the joints were all re soldered.

Finally back in use on the rack, Battery Terminal Voltages set to 13.8 Volts.

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My plumbing follows the physical convenience of the pipe run. I have just refurbished some basin taps (new insides).

A Morse Code H for Hot is easy, paint filled indents can be felt in the dark. Cold presents a problem a C in Morse Code is too complex. So I used an I. Cold Ice get it? I reckon there might be a connection in Ancient Latin there somewhere.

I could have made the I blue and the H red for kids and others, but NO, learn a bit of Morse or get the wrong product. There is a logical value code in there too to my mind, Hot is >than Cold.

Well it might also make a talking point for visitors.

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Replacing the bulb was a job I have put off for ages. Finally I pulled the controller apart. It is not easy to get at the scale illumination, just one bulb taped with a silvered tape at the top left hand corner.

Once all the necessary screws were removed to get access to release the scale it was obvious that the bulb had actually melted the plastic. An ideal candidate for cool lighting. There are positions for lighting provided at the top left and top right of the dial. I arranged 2 bright blue LED's in series with a 1N4001 diode and a 1K Ohm resistor connected to the original bulb supply. I secured my LED's with gaffer tape at the corners and re assembled.

The result is a very modern look for the trusty G400, plus the dial will not be melted by the LED's.

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There are some beautiful people who are keen on Linux and are willing to help and encourage the newbie. Back then I was fortunate to have Phil for the enthusiasm and Gena for the on air help, hours of it.

Then there are the Systems guys, some are great, some ride on a horse called Attitude in the 3.30 to Glory.
I was running TCPIP over radio. I contacted a guy and asked a question. "Don't you know the answer to that"? he replied in caps.
"Well, do you know if I knew the answer, I would not have asked the question".

It seems that around that time I may well have invented the term 'Attitude Jockey' every person I use to term to understands what I mean.

The Jockeys are still there, not only hiding under the Linux umbrella. They still ride the horse called Attitude, but that horse is always a loser.

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There are all sorts of pitfalls when compiling WSJT and WSPR. Some of the things effected are bizarre. For instance 'Program crashes when entering TX frequency in a box', problem goes when compiled with the old obsolete g95 Fortran compiler.

I don't even want to venture into reason and rights and wrongs, my natural feelings are toward the latest developments.

The Report Labels obviously are OK when compiled for Windows. Linux treats them differently, they wander round the GUI like lost sheep.
I have cured that with a GUI re design and I like it, all the 'keep your eye on' bits in one region. Believed to be stable on Debian and Ubuntu 8.10 here she is.

Right Click and Select View Image for full size.

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