WSPR is a mode which was purposely designed for QRP Propagation Study. The whole point is to radiate a known level constantly repeated signal and analyse the resultant Spots of that signal by disparate stations around the globe.

"But hang on there I see that T1WIT is getting Spots from America I had better turn up the Power until I do" is the logic often used. No propagation to W1LOUD using 100mW means that conditions are not favourable at that time, a valid piece of Data for Propagation Study. Turning up the Power until you get results invalidates all Data, as does not knowing what your Output Power really is.

Personally I can set a stable measured 10mW Output from my 100W Commercial rigs if I need to. I would much rather build a QRP Radio that consumes a few Milliamps for a few Milliwatts Out.
Ignoring the Computer consumption, on WSPR we have many stations with an HF rig consuming 60 to 100 Watts to produce 100mW of RF. What makes me smile is the fact that a Commercial Step Attenuator is then added to the set up to dissipate the power just generated.

The Elecraft AT1 or some other commercial Attenuator is listed in the equipment used as a modern 'badge of honour'.

Well at least the AT1 is available as a kit so you can have had a hand in this Modern Farce.

Why Cinderella?
In the week prior to the Easter weekend, having completed my Top Band MEPT I was looking at using a similar design for a 40m unit with my 7.00MHz Crystal. Then I received an Invitation to join DL6NL and G6AVK on 14Mhz for a Holiday Weekend activation.

I searched through my Crystals, all I could find was a 5th overtone one which on its Fundamental was out of the top end of the band. With just 3 days to go there was no time to order an Xtal so I replied to Peter DL6NL "thanks for the invitation to the Party but I have nothing to wear."

Going back to my 40m construction I wondered if I could select the Second harmonic from a Class C stage and get 14 MHz that way. I succeeded in getting a low level signal which was rather scruffy looking on the scope. I considered a Diode Ring Doubler circuit, fine if I was after a low level signal to amplify using several stages, not really simple MEPT stuff.

I moved to a digital Oscillator. Dividing digital signals is easy, doubling is not normally done, there is little information available on any techniques. If we were to put the 7.00MHz signal through enough digital gates we would get a delay of the signal. Apply the delayed signal and direct signal to a pair of XOR Gates and if the delay is correct we will get 2 pulses in one time period.
Alternatively a phase delay can be achieved with an R/C network both methods worked and on the day of the 'Ball' I was able to announce that 'Cinderella has sewn a new Gown and would be coming to the Party'.

I used the Gate Delay method in a bread board 'lash up' with a 2n222 Driver and BFY50 PA.

The 50mW TX fared well, conditions were not good but we were all copied (Cinderella and the Two Ugly Sisters) in Nova Scotia and Northern Utah.

I am below G6AVK and DL6NL in this capture into Utah a very thin signal barely visible but I was running 3dB less ERP and of course the antennas and paths are different.

Peter DL6NL announced the switch off time for his activity Noon on Tuesday. At the stroke of Noon my Cinderella TX disintegrated into a pile of components and a single Crystal (slipper).

I embarked on the permanent version, characteristics were different without the long leads I found a combination of Capacitive Phase shift and Gate delay with critical adjustment of the Capacitor gave precise linear results.

I used to despise Veroboard. Costly,Warping Paxolin and lots of stray capacitance between the rows, however it is quick and easy for IC projects and used wisely the capacitance can effects can be minimised.

The signal generation uses two 74HC86 IC's Selection of 7.00MHz or 14.00MHz is by the positioning of a single link.

Ideally suited as a PA is the 74LS240, having 2 separately enabled banks of Inverters. Band Selection is by a movable link for Enable and another for the Drive to either section. this means the BPF for each band can be permanently connected to its PA.

Separate plug in Band pass filters are used, this including a socket for the crystal means the MEPT is in fact universal and Multi Band.

Link swapping is no problem as the whole MEPT needs re setting when band changing, the FSK shift is doubled when the signal is doubled.

The MEPT is on its test run now using my spare PIC Keyer piggy backed on.

During the tests I tried a new method of Identification conceived to try and overcome the problem of missed identification due to missing parts of Morse Code symbols.

I now call this 5/5 It is 5WPM FSK Morse with a 5Hz shift. If I send my Call Twice and the two letters of my Major Locator Square this forms a Morse Code G in QRSS5 with a filled waveform.

Here it is into Nova Scotia, doing a fine job.

Manned Experimental Propagation Transmitter for Manned Experimental Propagation Tests.

A new MEPT band, for me 160 meters. I could build the same tried and tested design for all bands but the fun is in the experimenting. This Transmitter uses only 2 Transistors. NPN Crystal Oscillator DC coupled to a PNP Output Amplifier an ideal use for the old BFX29 transistors in the junk box.

Based on an old design from G3MY called the Pippin it is capable of more power than needed for a QRP Propagation Beacon. I used a DIP Switch to select collector load resistors. power levels from 5mW to 400mW are possible. The Crystal available needed pulling low, determined to use the bits from an Energy Saving Lamp I wound the inductor on the toroid former which saw previous life as the Lighting Pulse Transformer. The output capacitor and some decoupling came from the same source.

The other variation that can be made is in the construction method, I have used the Pad on Earth Plane method for VHF PA construction, it lends itself well to this project at the other end of the frequency range. I piggy backed my old test PIC Keyer to FSK via a Black LED once again used as a Varicap Diode.

Once complete I put it on test running 100mW to my 40m 1/2 wave Doublet, my e-mail being down I could not ask for reports, it would need to be spotted by a keen Top Band monitoring station, this was a week day and the week ends are more popular for 160m experiments.

When I managed to get some incoming e-mail a couple of days later I was pleased to see.

[Knightsqrss] who is on 160m? G6AVK

Later he searched the Captures for the most readable segment and deduced the call and QRA Locator. Well done and thanks Colin.

To start to understand the mechanism involved in the locking of two CMOS oscillators on the same chip we need to know a little about what goes on inside the DIL Packaged device.

Thanks to Peter G8EUX I now have an insight.

The 5 Ohm resistors and the 5nH choke which also has a resistance of around 5 Ohms are all inside the chip.

This is the description and circuit of my Diversity MEPT. I have used a 74HC86 as Oscillator/Buffer and 2 x 74HC240 as PA.

Right Click and select View Image for full view.

Due to the need for critical frequency matching I decided that the best approach was identical circuits on a PCB.

Right Click and select View Image for full view.

Sorry for the error. Pin1 goes to zero volts not +V

Run on 5 Volts and using just one gate in each bank of four on the chip and an output of 35mW the 74HC240's are not stressed.

When experimenting with oscillators using these chips I have noted that anything you do on any gate is reflected on all others, (via the power supply architecture on the chip I believe).
With the 74HC240 even enabling unused gates produces a positive move of the output frequency of a Crystal Oscillator which is using the other group of gates. I tried to use this effect to produce FSK of an Oscillator without the use of a Varicap Diode. It works, the snag being the shift is greater than we need for QRSS and the switching spike is huge.
Published designs using the 74HC240 for a single chip CW transmitter which keys the 'Enable' complain of incurable chirp, Hmm.

With the 74HC86 it is an opposite effect. FSK'ing of the Crystal Oscillator produces a mirror of the shift on the other gates.
I asked myself can we make use of this?
Yes, build 2 Crystal Oscillators on the same chip adjust the frequencies so they are close and they pull each other, get them very close and they lock.

Now FSK each oscillator 180 degrees out of phase, the positive shift of the high frequency one reinforces the negative shift of the other. This occurs when they are in a near fully locked state. Adjustment is tricky but once set up they seem to stay. The high oscillator with the positive shift becomes the master, if the frequencies are identical they fully lock, the Master will swamp the Slave, controlling its frequency to the extent of cancelling its shift.

Has this effect been noted before I wonder or is this the 'G3ZJO Lock'

The Oscillators are in fact adjusted to be 10Hz apart in frequency. The Master is set to say, 10.100000Mhz, the FSK shifts it to 10.100005Mhz.
The Slave is set to aprox 10.0999990Mhz the FSK shift is adjusted to be aprox 2.5Hz. When pulling takes place this shift is reinforced to 5Hz, i.e. to 10.100000Mhz.

The Locking and shift reinforcement can be seen in action in the following picture. The two oscillators started in lock, the PCB component side was sprayed with freezer concentrated on the Master Oscillator. The Master (top trace) is seen gradually approaching the Slave as the temperature recovers. At 130 seconds from the left hand side of the display the two carriers are seen beating together, after the next shift they lock, shaky for 45 seconds, then solid.
Note how the FSK Slave shift increases when in this state.

Right Click and select View Image for full view.

Very cold starts can be a problem if the Slave starts a little too high it is swamped requiring a finger to be poked in to pull it low. (A re-set button could be provided.)
It is still early days but at normal ambient temperatures start ups are perfect and 16 Hour periods of lock have been maintained using both breadboarded and the final PCB version.
In striving for minimum bandwidth (10Hz shift) I may be running the system too tight, tests are continuing with both oscillators set for about 5Hz shift prior to locking them. This results in a final shift of around 12.5Hz, it may avoid swamping as the FSK will force them further apart.
08.03.2008. Further I have found another lock, tighter than both previously described, when in this state the negative shift can be turned to zero level. Tests will continue to establish the long term stability of this. Maybe we are getting only the mirror of the positive shift.

When testing on the breadboard I switched off my bench light and the lock went haywire, this lead my the use of Black, Infra Red LED's (ex TV remote controls) in place of the Visible Red LED's normally used as varicaps.

The use of two 74HC240 for the PA may be an overkill, I didn't try using two halves of the same chip as I was aware of the undesirable effect mentioned above. They cost less than .5Euro each after all.

Another extravagance is the use of a LM7805 Regulator on each unit, again at 1.5Euro for a bag of 15 we get super regulation and isolation.

PA PCB Print View.

Osc. PCB Print View.

Finally the PIC Keyer, everyone has their own favourite method of generating FSK we just need two 180deg. outputs.

PIC PCB Component View.

PIC PCB Print View.

Where can I get a T50-2 and some PCB Material, Coils, Xtals, IC's and Resistors, Capacitors etc. all suited to Amateur Radio use.

JAB that is where, I have been using Peter lately for my component orders. Speedy and efficient with a personal touch thrown in. A Radio Ham at the other end is a great asset you know.

I have known of JAB for some time, I should have used them sooner.

Look them up on the web.

JAB Electronic Components for Radio Hams & Hobbyists
Welcome to the home page of. JAB Electronic Components. ... JAB Electronic Components PO Box 5774, Birmingham B44 8PJ UK Tel 0121~682~7045(Answer Service at ...
www.jabdog.com/

A change from the usual tone of this blog.

Back in the 1970's in our little village in Northamptonshire things were quite different from today. A-10 Tank Buster Planes would appear over the houses at 7.00AM and mount an attack on the Local Railway Station. 'Oh no they do not', said the Commander of the nearby RAF/USAF Air Base.
One morning one of those planes turned back after the mock attack and did a Victory Roll just above he houses at the end of the road. 'Never' said the Commander 'any pilot that did that would be instantly dismissed from the Services'.

Daily at a regular time in the morning a Low Flying Twin Propeller Plane with a large pod added under the nose would fly low, East West. In the afternoon back she would come. Its path took it over my Allotment Garden Plot. One day it appeared flying so low that I looked up as I dug the ground with my Fork, I followed its path above my heard and lost balance. Knocked off my Fork by a low flying aircraft.

Clearly we were a strategic area for some reason and surveillance was being carried out.

My QTH was between the path taken by the Survey Plane and that of the Tank Busters. I mention this to add another dimension to an Aliens story.

There is a Magic Length for a Top Band 160m Antenna, 150 Feet, end fed. This can be tuned with a 1000pF variable capacitor. I devised a method of attaching the centre of an inverted V arrangement of such a wire to the top a mast at the apex of the house. This doubled back to the house at either end and was anchored to a post at the rear and a tree at the front of my garden.

I popped it up on my Saturday off. It tuned beautifully and worked really well. I went to bed happy with my new antenna that night.

At 5.00AM we were awoken by a high pitched noise, bleary eyed I stumbled to the shack thinking I had left a radio on, as I approached the shack I could tell it was not from there, it was very directional and there were peaks and troughs as I moved around.
My next thought was to check the TV, the Off Air test tone was much lower in frequency than this one but I had to check. As I descended the stairs the noise vanished returning as I ascended. Outside, I thought. I flung open the window which faced the front garden, as I did my neighbour opened his too.
"What are you doing", he said.

"I was going to ask you the same thing", I said.

It was very misty my new wire antenna was dripping with condensation.

"It's that aerial of yours", said the guy next door.

"No way", I replied.

"Well then", he said, "I looked out of the back it is that Power Company Transformer, I am going back to bed". He was a Geography Teacher not into anything at all technical.

"No I don't think so, but I can't explain it" I said.

I went back to bed too the noise carried on for some time then went away. We discussed it in the morning, I asked people who lived opposite, they heard nothing. We never heard that noise again.

I might have completely forgotten that episode had I not met a neighbour from a house at the rear. We met in town, typical, you do not see people who live quite near, This guy worked shifts and through the week ends.
"Hey", he said did you hear anything last Saturday early in the morning, I was on an early shift, I left my house and there was a high pitched noise above your house, do you know, it worried me, I didn't like it, I went back in the house and did not leave until it stopped, I was late for work".

"So it was nothing to do with the Supply Transformer, that is on your property."

"No definitely above you house, there was a heavy dense fog so I could see nothing".

Still this story may never have got told, had I not met another neighbour from some 150 Yards up the road, again in town and about 10 days after the event.
"I have been wanting to talk to you", he said. "On the Sunday morning before last I was going out early, poaching actually with my shotgun. I loaded the car and looked down over your house, there was a brilliant light, huge it was, I must admit I was scared, I thought it was Aliens, I got in my car and drove off in the opposite direction."

"Any noise", I asked.

"No silent and very misty", he said.

I have built and run two Manned Experimental Propagation Transmitters on 10.140073Mhz to enable myself and others to observe the propagation conditions on that band.

I decided from the outset that I would use a PIC microprocessor to generate my call sign for identification purposes. Thus positive identification should be guaranteed.

My first MEPT used QRSS3, three seconds per dot Morse code. Soon it was recommended by stations in Australia to use QRSS10 for greater readability with lower signal strengths.
I thus used QRSS10 for a long period.

When looking for my own signal on the WWW network of Grabbers I sometimes had much difficulty with positive identification. I have even looked at a Morse ident and managed to fit my call letters to it only to realise after a time that it was a Capture from 40 meters and my signal is on 30 meters.

This can arise due to fading which causes parts of the Morse code to be lost. All stations running QRSS10 will be producing dots spaces and dashes of uniform length, many combinations of received elements can fit an expected pattern if some parts are lost.

Compare this with the simple Ramp, Sawtooth or Squiggle used by some stations. Providing the characteristics of the Squiggle are unique the signal can be identified with much less information.
"It is the correct Frequency there is a Squiggle therefore it must be 'X'."

Squiggles are used because they are a simple KISS approach to identification. I was thinking about building a new even lower power MEPT and considering KISS identification. Could I generate square waves with a 3 to 1 Mark Space Ratio and gate just 2.333 of them out as a 'G' in Morse.
After some experimentation I settled on an LM555 oscillator with a 27 second cycle and equal Mark Space Ratio for character timing. This signal Triggers and Gates another LM555 which generates a 3 Second Mark 1 Second Space square wave train. The use of Mylar timing capacitors ensures stable timing which has not wandered during long 24/7 test periods.

I added a long rise and fall time to the FSK modulation to give unique shape to the waveform. Another identification feature arose due to the first 'Mark' after 'Trigger' being slightly longer than the next, a feature I eagerly retained.

'G' MEPT uses two chips 74HC240 and LM556 to produce 25mW of Morse identified Beacon

OK there are 3 chips, I had no LM556's in the Junk Box.

I have again used the concept of the 'Crystal Cool Box' as opposed to a Crystal Oven. An oven could be consuming more power than the complete transmitter. The Crystal is hermetically sealed in a Polyurethane Foam Cube.

Long term temperature stability is very good using this method. The 'Cool Box' has come of age in this light weight version, the Cube being lined with adhesive Aluminium Foil. The outer box in previous versions was made from copper clad PCB.

The initial on air test produced a report from Belgium.

Quickly followed by New Zealand.

Italy

Nova Scotia

Netherlands

France

There is a screen grab elsewhere showing the 'Hole in the Middle' of my Softrock TX/RX display. I used YouTube as a resource for storing my videos to use here, now they are a collection in themselves, hence I have produced a video of the 'Nothing'.

There are some hideous Humps displayed by some users. Using the Delta 44 Sound Card provided the construction of the RX avoids loops, it is possible to obtain a 'Hole in the Middle'.

OK then whilst I still have my guns loaded lets have a blast at Packet Radio then we can go a bit more positive with the posts.

I still run Packet Radio despite the fact that it has almost become the domain for a few cranks only. I returned from France this summer to find the regulars in an out and out character assassination of one person.

I was amazed at some of those involved, they instantly went down in my estimation, so far removed were they from the Gentlemen of Radio that I used to know. I don't know how it all started but to me it resembled Jade Goody in the Celebrity Big Brother Pig Sty, I just had to post a message on the Bulletin Board to that effect.

I was a late comer to Packet. One thing that put me off was that awful thing the TNC. Once there was the possibility of a Software TNC I joined the throng. Why is the TNC awful? Well it is like the Soundblaster Interface totally unnecessary. I did let one into my shack once it generated so much noise in the 2m Band it rendered it unusable for
low signal work. It is mode specific to the extent that many Packet folk tie up a Radio and a Computer just for Packet. Many TNC's are so old that the parameters have drifted and they cause many a frustrated operator.

When our local packet BBS went off air I set up a BBS and Node here with 2 TNC's ready for installation elsewhere. All I can say is, it was interesting but I was really glad to see the back of it.

Me, with my Software TNC, well I can be doing 6m Meteor Scatter one minute on the same Computer and Radio, then Packet the next minute all on the same famous THREE BITS OF WIRE.
Hence I sit and scratch my head in wonder what this unit is for.

Right Click and select View Image for full size.

Is that not an FT817, it has Data socket, why do you have to unplug the Microphone?

It does not isolate the Computer Audio Input whereas the Computer Output is isolated by a 600 Ohm Transformer and the PTT line by an Optocoupler.
I was prompted to look at this unit when a Ham reported blowing both his Transceiver and Computer Sound Card when connecting one up. Intrigued I looked at the circuit diagram and the danger is obvious. If there is a PD on the Rig Ground and you touch the computer Input or Output jack centre pin to it whilst plugging it in you apply the nasty PD to the computer.
Fifty Quid well spent I would say, not.

I have never liked the Flex Radio Software, I looked at it long before I had an SDR receiver to put into it. I thought that perhaps given proper I and Q inputs it would perform more to my liking. Not so. Here I will show some of my personal dislikes.

The Spectrum display is imprecise.

Here I hunt down a CW signal and try to follow the Morse using Spectrum Display 'real time' and with Averaging.

Using other software it is possible to read Morse Code directly from the pulsing of the incoming signal, and so you should. I find the lack of real time display unnerving.

Here I hunt down an SSB signal zapping down the band with the Mouse like I do on Rocky software.

I have seen another You Tube video of Flex Radio and it did the same as I find, tune rapidly and the display collapses, the very signal you are heading for has gone, you go past, stop and whoa it appears behind you.

Over the years I have been asked to write an article on Sound Card Interfacing, I have always resisted.
On the air I admit that I taunt those who have spent hundreds of Pounds/Dollars on commercial Interfaces instead of using "3 bits of wire".
I have been astounded to see the inconveniences endured by those who have paid out the small fortunes too. Unplug the Microphone from the Rig and plug in the Interface when you want to change from Phone to Digi Modes, wow that is well worth paying good money for.

Recently I ended up on some pages on the web dedicated to an interface design, I think there may even have been a Yahoo group. Was there really a Lecture Circuit too at one time? I began to wonder just how many Billions of words have been written on the subject, how many thousands of videos, how many Millions of pounds profit made by companies. Yet I cannot remember one mention of Safety.

We and our neighbours go out and purchase a Hi Fi Amplifier a Recording Device, Computer and a Radio Tuner and think nothing of connecting them together Output to Input etc. Why? well they are designed to be interconnected. Well so are our Radio Transceivers, particularly the modern ones which have a data socket.

Why do Radio Amateurs panic when they want to connect their rig to a computer. Well you can 'Blow up the Sound Card and the Radio' yes that is true but that is due to lack of Good Practice. That lack could kill the Amateur.

Also you could get RF Feedback into the computer Audio, yes true, but will 600 Ohm transformers prevent it, not necessarily, whereas a common mode choke, (winding the screened lead on a Ferrite Core) probably will.

What the transformers will do is drastically limit the Audio Response, may be a cause of some problems in the past, certainly a disaster in modern radio SDR systems.

Anyone familiar with the Icom IC706 (the rig that receives on the frequency on the dial and many others at the same time and sucks more current on RX than 3 other radios put together; but that is another story), will be familiar with what I call the Shaving Brush. A Din Plug for the Data Socket, supplied ready wired with a couple of inches of multi core screened cable, outer cover removed for an inch or so which looks just like a brush with multi colour bristles.
Some years ago there were many IC706's locally, owned by new Licensees. I was asked to provide details of utilising this for Digi Modes.

I photographed everything provided drawings, parts list and write up. I handed the draft to one keen user who was technically knowledgeable. One criticism, came the verdict, you spend more time, a whole A4 page, writing about Safety before you get down to the Interface, we wanted you to write about Interfacing.

There is my point.
Good Practice will prevent nasty voltages which will destroy the Computer Sound Card or Radio, as a small bonus it may save the Operators Life.
Good Practice will eliminate Ground loops and the need for Transformers.
Good Practice will prevent RF feedback into the audio circuit.

The big difference between the Domestic set up mentioned above and the Computer in the Radio Amateurs Shack is the fact that the Amateur is most likely going to be bringing Real Earth into the Shack and the Radio. He then is going to connect this Earth to a Computer which in the UK is most likely to have its 'Earth' connected to the Neutral of the Mains AC Supply. This Neutral is the centre point of a 415 Volt 3 Phase Supply. Under fault conditions, which I have experienced at this QTH when the underground cable Neutral failed, this can be lethal.

For Safety do not have both Mains 'Earth' and True Earth anywhere in the Shack, I leave you to implement this, or get in a professional to help. I want neither wrecked Equipment or dead Hams on my hands.

Pay 100, 200, 300 Pounds for your commercial interface and it may or may not protect your Sound Card and Radio. It will not protect your or others lives. You still have a potentially Lethal Shack.

For this reason I have not and will not mention Interfacing without dire warnings.

OK I simplify just a little with my 3 bits of wire statement, only the other day someone thought for a minute and said, not 3 bits of wire you mean 4. No I don't, the wires are screened lead. Think about it though, you do not want to produce earth loops.
Also there is a need to level change the Computer Serial port for the Rig PTT so we must add a Transistor 2 Diodes and 2 Resistors. This circuit is already published in dozens of places on the web. I just build it into the 9 pin Serial Port plug and forget it. For portable use with my Lap Top computer I required a low profile arrangement. I therefore potted the circuitry onto a skeleton plug. The top of the Transistor can just be seen through the potting.

Off you go then down to the Ham store, pay half the price of your Transceiver for a commercial interface, most modern Hams do.
Whilst you are out be sure to get some good Rubber Gloves and thick Rubber Sole Shoes, always wear them in the shack, have extra pairs ready for any visitors and invest in a good Fire Extinguisher.

Yes some of my postings are meant to promote thought and discussion.

Intriguing Indeed. Take a look at this AM Intruder on 40m.

Living within 1.5Km of a Local Medium Wave Broadcast mast I have become used to the odd AM clatter on Top Band and higher.

This particular 'Moronic Music' was getting just a bit too strong and persistent and attracted my attention particularly on the SDR receiver.

Shortly after making the recording above I decided that perhaps I should endure the constant 'Moronic Music' to await a station ident. I wanted to find if it was a) A harmonic from the local mast. b) A pirate. c) A local receiver radiating. d) Something in my station.
One morning the Moronic Music changed to Virgin Radio and shortly after to Northant's Gold. Northants Gold comes from the local mast and is on 1.557MHz.

There was no way I could make the maths fit for a harmonic to show on 7.02670 MHz nor would any LO radiation from a receiver fit mathematically.

One thing at my station that has been in operation again for maybe the same period as the Intruder is my QRSS MEPT Beacon on 10.14070. I listened on 7.02670, flipped the switch and off went the intruder.
Now the maths fit 2 X 1.557 = 3.11400MHz. 10.14070 - 3.11400 = 7.02670MHz and yes there is a signal also at 13.25470MHz

The PA in the Beacon TX is Digital. Was a mixing taking place here? I changed to my Analogue TX, no change.

When I installed a 40m Hairspray Antenna in the Loft Space along side the 10 MHz Beacon Antenna I expected the intruder to be very strong. Wrong, it was non existent. This proves that it is not the Beacon TX or it's antenna involved in the mixing.

I therefore suspected my 40m Doublet Antenna to be the one that was doing the reception of the 1.557Mhz signal, to mix it would need a non linear device. It goes to my MFJ Antenna Tuner which of course has Diodes in its Power/SWR meter circuitry. I have never come across this problem but it was a possibility. I also have an MFJ Portable tuner, I swapped the antenna over, no Intruder.
Checking the circuits of the two MFJ's they are virtually Identical, did we have a fault in the first tuner?
There is not much external to check but before I disconnected the Ground leads I removed the link which connects one of the Balanced input Terminals to the Unbalanced Input Terminal and replaced it with a short length of silver plated wire. Intruder GONE.

We have heard of the Rusty Bolt Effect the Corroded Razor Blade, I give you the Still Shiny under the terminals Copper PCB Detector.

Previously when I had to remove the link to use different antennas it was much easier to handle than a wire link. Since purchasing the MFJ Portable Tuner, (just over 1 year), it has not been disturbed.
The tuner with the link is in daily use, I have not noticed anything detrimental on RX or TX due to the problem the link had developed.

Today I tested the 40 Meter version of the Hairspray Antenna. In its test position on the dressing table, (yes the XYL was out again) I called a few stations who admittedly were not very strong on Receive. Using the theory that it is always worth a go. Well it wasn't.

Soon the time for my PSK31 sked came up, swapping to the Hairspray the RX signal was solid. The set up on the Hairspray was completely separate and the TX power at least 10dB down. Would I be heard over 700Km away on a 400mm antenna? Yep about 15 to 20dB down but solid copy when the QSB didn't cause problems.

Why produce antennas that are usable only on one band, asked F6GUU.

Well these two antennas are for single frequency use. Here they can be set for resonance where they will be at maximum efficiency. One for my 10MHz QRSS MEPT beacon, the other on 7.036 MHz for Data use, so releasing my other more frequency flexible antennas for other uses at the same time.

Here is my Choke Balun I made for use on the 10 MHz Version.

The Hairspray Antenna is now mounted in the Roof Space of the house. So how does a Loft Antenna 400mm long perform on a band where a 1/4 wavelength is 7.5 meters. Yes it has a feeder but then so do most Antennas.

Amazing, my 80mW 10MHz signal was the only one in the world that I saw getting into Italy and that was so for most of the day. It also crossed the borders down into Cornwall on and off today.

This screen grab is from yesterday when I had a companion.

Who remembers that advert then?
Today I got some new coax so that I could cut the feeder to the exact length for my 10 MHz Hairspray Antenna.
This is where I really have fun, constructing and testing antennas.
The Hairspray is an EH design as opposed to a Magnetic Loop antenna. The whole 'active' part is a vertical only 400mm long including its support tube and Coax socket. Yes that is 400mm a quarter wave vertical for that band is 7.5 Meters so it is definitely a 'shortened antenna'.

The whip at the top is shown fully extended it is for exact trimming only. I have constructed the antenna so that it needs about 50mm of whip for resonance, thereby ensuring that whip current does not play a part in the operation.

So I cut the feeder fitted a PL259 plug connected the Choke Balun and feeder to my QRP QRSS Beacon Transmitter. For initial test I popped the antenna on the dressing table in the bedroom with the feeder along the landing to the shack. Yes the XYL was out.

A pretty in-efficient antenna installation. So yes I was pleased to see my 80mW TX getting into Italy on the Italian Grabber. Next step an outside perch after waterproofing and corrosion protection then testing of the 7MHz Alberto VO5 antenna.

Computer problems in France have caused delays in experiments with JT2 Mode. My signals were decoded and replied to by an anonymous commenter who it seems considered that we were running the 'WRONG MODE'. I know what he meant, I was testing on my beacon frequency on 10.140070 'ish. Beaconing with a mode that can be replied to could attract fools who will reply, and he did.

The Laptop which I delivered two years ago to France refuses to decode any JT2 signals. Today the Tower Computer was pressed into duty and reports were exchanged. F6GUU carried out local tests from one machine to the other last night, always a good idea with a new mode I feel. He proved the Laptop system works one way but not the other.

If you try new modes with a local station you need someone with trusted equipment and reliable knowledge base of techniques. Too many times I have been told that my signal is no good and cannot be decoded by someone who has not set up his own station properly.

One only has to view the 'slant merchants' on SSTV. Transmitting slanted signals and telling incoming stations that they have slant.

Winrad software presents an extra problem for producing screen captures. Don't worry your one eyed, one legged, aged technician has conquered both that and getting the program to run in the first place.

Winrad versions are built to expire and be replaced. If you try to run a version after the sell by date you click on START and it dies. I installed a new version and what did it do, just as described. Now if your computer date was wrong when you started the program you would get this, my date was correct.
I have run previous versions and it is a superb piece of software so I was a little peeved.
I run software on XP under two accounts one with full privileges one without, it would not run on either. I may have done my first run without admin privileges, did this cause the problem, maybe. The cure for running with the wrong date is to download and re install the latest version as a last resort, I tried it, it worked.

It is a pity the definition of the software defined radio video is not a bit better once it has been YouTubed. The display of several different Data Modes in the bottom window is superb. Here we also look at SSB too.

Sorry it is short I have to keep the file size down.

Next Morse code, I change the LSB filter to CW and re position the filter curve on the signal.

Again short but I hope sweet.

Winrad software is superb for analysing signals over a wide and narrow band width.

Comparing the background noise on my Dual Core high spec. Laptop which has a Realtek HD Sound card with no audio input.

With my Celeron processor desktop with Delta44 Sound Card set up exactly the same.

Speaks for itself .............. literally.

Yes there is a volume difference due to my recording process on 2 different set ups. On the second one there is a much louder nothing.

Very much in the spirit of Amateur Radio an international symbol of peace accompanies the beacons and my JT2 signal today.

For those who know not of the antics of radio the Blue background is a small portion of the Radio Spectrum. The White dots are Noise. The Dove is a signal switched on and off and moved up and down to literally write in the Noise.

A little later and here is my signal less than 1Watt power into Australia.

Having been away for a week I could not wait to get on with the new mode JT2.

Ideal for weak signal work on HF, the bandwidth (as long as you do not send a Morse Ident) is only 8.75Hz.

Some QRSS Knights have been testing the mode, I have seen no contacts reported so it was time for a CQ call or 1000.

Using 5 Watts in the afternoon I could see my signal in the Netherlands, Belgium, UK, Singapore and Canada.

I dropped power to 0.7W and still was fine into Canada as the capture shows. All I need is someone set up for the mode at the other end and we should have communication.

The 3 postage stamps near the top of the display are my minute long bursts of data.