Portable Pains

I have just returned from our traditional June caravanning holiday in the Lake District, last year I was buoyed with enthusiasm to have a go at some more portable operation after operating for the first time from the camp site during the 2m UKAC Contest with some encouraging results.

Indeed during the last twelve months I have done some more portable operating, but while VHF/UHF have been rewarding HF portable has been a mixed bag with at best satisfactory results, but then the same can be said of operating HF from home.

This year I planned to again operate in the 2m UKAC Contest but rather than working from the comfort of the caravan I was going to work from some higher ground near the camp site. Unfortunately the weather was awful with very strong winds gusting upward of 50mph and driving rain, even working from the caravan was a no go.

So rather than enjoying this view with a microphone in hand…

… this was the how I spent the evening and as you can see Eddie was equally impressed.

 

When the wind and rain subsided toward the end of the week we did have some nice weather so I decided to try some HF. I had taken just the M0CVO Magitenna end-fed wire and using a 9m fibreglass pole I tried operating with it as a vertical and as a sloper both with and without counterpoises and despite receiving some very big S9+ signals on a number of bands seemed to be incapable of making myself heard, I did make a number of contacts but many reported weak signals and stood little chance of working many of the special event station pile-ups.

It wasn’t helped that on the first day the radiating element connector broke, which necessitated cutting it off and stripping back the wire. I suppose in retrospect I should have been expected it as there is no strain relief on this wire, unlike the loops on the other antennas in the M0CVO range, I rectified this with a few cable ties.

I was running the Yaesu FT857-D from a leisure battery and around 30W as I didn’t wish to interfere with the TV reception as I knew most caravans would be using wide-band antenna amplifiers because of the poor coverage. Indeed the one time I did wind the power up to 100W one caravan mains breaker tripped out, it may have been coincidence but I didn’t wish to put it to the test.

Despite the lack of performance it was great just sitting under the majestic Skiddaw and surrounding hills while I spent a few enjoyable hours operating. I even discovered one of my neighbours was also licensed, nice to meet you Joe (G4LIA)

It was frustrating from a contact point of view and I willingly accept I could be a bad workman so don’t wish to blame my tools but I think some serious rethinking on a portable HF antenna is needed. I am away to Scotland next month for a week on the Isle of Skye and a week on Islay, this time in rented cottages and am hoping to make a QSO with the South Kesteven ARS on the club night.

Anyway that all has to wait as the launch of Eggsplorer-1 HAB and the GB2EGG Special Event Station are rapidly approaching.

Portable in a very windy Cumbria

Before amateur radio took over my life my main pastime was competing at dog agility which I did moderately successfully for many years, for several of those I was even the chairman of a Nottingham Agility Dog Training Club and organised one of the larger Kennel Club Championship shows as well as judging at many events. If you search my YouTube page there are a number of videos showing me and the dogs in action.

Things change and sadly I became disillusioned with the sport as seemingly endless rule changes and its increasing popularity saw it losing its core ideal, what was meant to be fun for dog and handler had sadly become too competitive, professional and commercial, too many people now make money out of the sport and what was once an enjoyable social activity is now spoilt by unsportsmanlike behaviour, complaints and bitchiness.

When my dog Boris suffered a cruciate injury the enforced time-out made me realise I didn’t want to do it anymore and so I don’t.. well apart from the odd exception, last weekend was the West Lakes Agility Club Show held in the small town of Haverigg on the Cumbria peninsula (Locator IO84IE)

This is a lovely old-style small friendly show with the bonus of being held just a stones throw from the sand dunes and beach. I had agreed to go and like the recent holiday in Skye it was initially planned with no thought for any radio operating.

We would be caravanning at the show for the best part of four days without any electrical hookup and the wife had volunteered to help on Saturday leaving me on my own for most of the day… so a plan was hatched at the last minute.

I purchased a nice new ‘spare’ 100A/h leisure battery and smuggled on board the FT-857D with some suitable battery clips, headphones, a fiberglass pole, some antennas. I don’t own a suitable ‘portable’ ATU at present,  having borrowed one from SKARS on several occasions but as this was a last minute thing I would have to chance operating without it. I took the M0CVO HW-20P OCF-Dipole, which has a usable VSWR on 20m, 17m, 15m, 12m and 10m without an antenna tuner and the M0CVO Magitenna, but wasn’t sure what I would get from this as I’d only ever used it with a ATU.

The weather was difficult all weekend, we arrived on the Friday to be met with warm and sunny conditions but a steady strong wind. There was bit of a battle to get the caravan awning up but we managed it.Saturday the wind just got stronger, the forecast for Sunday was for even stronger winds so it was dismantled and packed away, indeed it was worse around 25-30mph with must stronger gusts.

Undeterred I got the antennas up,  however the fiberglass pole I have must be getting on for 10 years old, and would often fly a pirate flag when camped at agility shows. It had already lost it’s top section many moons ago but was still quite tall and so I hoisted up the OCFD balun and coax and the end of the magitenna wire in the buffeting wind and it was swinging around wildly – almost inevitably it proved too much and the remaining top section splintered!

Despite losing over in a metre in length I tried again and managed to get everything up, the OCFD wires were tied out to form a sort of inverted-vee using a handy nearby fence, the Magintenna was pulled to form a sloper across over the front of the caravan, but due to the lost height actually touched the front of the roof. Amazingly I got an almost 1:1 VSWR on 40m and loud and clear RX.    

This weekend was the International Lighthouse and Lightship Weekend (ILLW) this annual event has been going since 1995 and promote public awareness of lighthouses and lightships and their need for preservation and restoration, and at the same time to promote amateur radio and to foster International goodwill.

The bands were kind and I had an enjoyable Saturday afternoon and a few hours on Sunday making QSOs with a number of UK and European lighthouse stations on 40m and 20m and it seems the whole event was a great success. Alas the wind proved too much for the remainder of the fiberglass pole and it developed a large crack in the bottom section forcing me off the air.

By coincidence Haverigg has two lights, the old Hodbarrow beacon and the restored Hodbarrow Point lighthouse (pictured above from the beach). Last year we walked to the restored lighthouse but since the restoration was completed in 2004 it is sadly looking in need of some remedial work.

I only learned of the ILLW event at the last minute and sadly neither of the Haverigg lights were activated that weekend, next year if the show is on at the same time I may look at trying to operate from them.

Oh and the wind? Here is a video of a walk on the beach on the Sunday morning..

Noises Off – WiMo QRM Eliminator

As I posted at the end of June I was almost on the point of giving up on HF due to the high levels of QRN/M suffered at home.

In desperation I had been looking at some of the noise cancellers available from MFJ and others. I had heard conflicting options on their effectiveness but was willing to try one if I could obtain one cheaply. The MFJ units are in my opinion expensive to purchase new so I bid on several that came up second hand on eBay but they invariably also went for silly money. I was even contemplating building an home-brew one from the numerous designs available.

Then I discovered the WiMo QRM Eliminator, made by the German company WiMo Antennas and Electronics. Several online reviews and numerous YouTube videos seemed to indicate its effectiveness and taking up the then summer discount offer I ordered one for the princely sum of €147 including postage, around £116.

Due to heavy demand and low stock levels following the International Ham Radio Exhibition at Friedrichshafen I was told the unit wouldn’t be available till the middle of August, so I was pleasantly surprised when the unit turned up last Friday morning.

New toy in time for the weekend 😉 Thank you @wimo_de pic.twitter.com/4Xfuv5ccHB
— Andrew Garratt (@nerdsville) August 1, 2014

I have connected it up and briefly tried it out and am impressed, as this video illustrates.

Even using one for a short time I would agree that they are something of a black art to set up and use and can understand why people might consider them useless, but this may be due to lack of understanding of how they work.

I have created a diagram showing a typical scenario.

The operators main antenna is designed to pick up distant signals, not necessarily DX but signals not emanating from the immediate vicinity, however they will also pick up locally produced QRM as shown, perhaps generated by a neighbours TV or PLT device. 

The QRM eliminator has a second antenna which isn’t as efficient as the main antenna and ideally just receives the local QRM at a similar level to the main antenna. The device then takes this second signal and inverts the phase so when it is mixed with the main antenna signal the QRM is cancelled out.

The principal is quite simple, if you take two in phase signals and combine them you will end up with a signal with a larger amplitude. However if the signal is 180 degrees out of phase, the positive and negatives of the waveform cancel each other, producing a null signal. 

The tricky part is making sure the noise antenna just picks up the noise, if it picks up the main signal then that will also be cancelled out. The WiMo unit has three controls a gain and two phase controls it is a case of altering all three to maximise the cancelling effect without losing the main signal.

At present I just have several meters of wire running as the noise antenna along the side of the shack and this seems to fairly effective.

The unit is powered from 12V and can be left in line, but requires the PTT/TX-GND signal from the CAT/Linear socket from the transceiver to activate a bypass when transmitting and I don’t have the appropriate 8-pin plug at present. If the unit is powered off the bypass is automatically engaged.

All in all, first impressions are good and looks like a worthwhile purchase.

Skye Activations? Remember the 7 Ps!

As the military adage goes “Proper Planning and Preparation Prevents P*** Poor Performance” well I have fallen foul of this in getting ready for my imminent holiday to the Isle of Skye.

Last year we went back to the Isle of Skye after our first visit over a decade ago.  We rented a self catering cottage near Dunvegan and a great time. The scenery (and the whisky) is spectacular and the dogs loved it, so we decided to go back this year. 

The cottage
The view from the cottage
The tasting experience at the Talisker Whisky Distillery

The cottage is no longer available for holiday lets, but we have found another which promises even better facilities. Last year I wasn’t licensed, so this time I planned to take the rig and operate from the island.
  
The holiday coincides with the 50MHz/6 Meter UKAC contest and the opportunity to operate from the rare IO67 locator square was something I was looking forward to, I was totally realistic as to my chances given my set up, the terrain and power restrictions.

IO67 Locator Square

I planned to build a quad beam, there are plenty of designs on the web and ordered some fibreglass pole to make the spreaders but over the past few weeks have got sidetracked and left the construction till the last minute and it has turned into a disaster!

I abandoning the idea of a multi-element quad beam once I realised the sheer size it would be and the lack of space in the car and so opted to make a manageable two element quad.

I modelled up the antenna in MMANA-GAL to check the dimensions, made a nice short wooden boom, and cut the fibreglass pole for the spreaders, initially cutting them all to the wrong length! Cue expletives!

So I cut another set to the correct length and made the wire loop elements and tried to put it all together. Unfortunately the fibreglass spreaders are far too thin and bend and sag under the weight of the wire! Cue even more colourful expletives!

Plan-B is now just a simple tuned dipole and all I can hope for is some Sporadic-E on Tuesday evening!

I am packing the HF antennas a Magitenna and the HW-20HP from Nigel at M0CVO Antennas. I haven’t done a great deal on HF finding the operating a little intimidating however I will endeavour to be on air during the week having realised in the last couple of days that I can ‘activate’ the island and some ‘rare-ish’ grid squares for the Worked All Britain (W.A.B) scheme, as well as ‘activating’ for the Island On The Air (IOTA) scheme. I might convince the wife to let me take the rig portable on a planned trip across to the Isle of Raasay for another activation.

With just 48 hours left I am rapidly reading up on what I need to do… as my wife pointed out I have had weeks/months to prepare for this… the 7Ps indeed!

If I do get on the air as 2M0NRD/A or 2M0NRD/P during the week please be patient and treat me gently! I will be on voice and maybe JT65 and PSK. The cottage has wi-fi so will post updates on my twitter feed @nerdsville.

Noises Off!

Radio frequency interference (RFI) is the bane of a lot of amateur radio operators. Sadly it is becoming a real issue at my QTH.

RFI is referred to as QRM or QRN and I am learning the difference.

QRM means “I being interfered with” and is interference coming from someone using radio equipment. This covers deliberate jamming, people tuning up or just normal operations on a crowded band that causes QRM.

QRN means “I am troubled by static” and technically means interference from a natural noises but has come to refer to interference coming from anything that is not an intentional radio emission and interferes with reception of transmissions. So now covers atmospheric noise, static or the noise generated by electronic devices.

Noise isn’t a new issue here as I have posted before. It has tended to be sporadic and bearable but since becoming licensed I have become more sensitised to it. Until now I have tended to focus on the VHF/UHF side mainly contesting venturing only briefly onto HF.

My HF set up is limited at the moment with just a single antenna which isn’t optimal for the lower bands. Due to the day job I am largely restricted to evening/night time operation when the upper bands have largely been closed anyway so haven’t really attacked HF with much enthusiasm apart from data modes such as JT65 and WSPR which have immunity to noise.

When I have got the chance for some early morning daytime operation or at the weekend I have struggled with noise.  Recent weekends have seen some special event stations operating for the Museums On The Air and the GB1JSS Summer Solstice which have been predominately on the 40M band but I just cannot hear anything on that band due to noise.

I am aware the Sun has been particular active recently producing a number of large flares and CMEs that have caused a number of radio blackouts, but this noise isn’t due to atmospherics I am certain it is man made by one of neighbours.

I made this video last weekend

and this video was from the weekend before that

This weekend was the 50MHz Trophy Contest which I was looking forward to, sadly it was also to become a victim of the QRN as this screenshot from my SDR will confirm, for much of the time I was operating I was just listening to noise.

I wasn’t operating constantly, just grabbing a few minutes here and there and I did manage to make some decent contacts when the QRN subsided even catching some of the sporadic E opening to get EF7X in Spain.

I have ruled out any noise being generated by myself by powering everything off and running on battery. This leaves me in a bit of a quandary I could go around and locate and confront the culprit or even contact OFCOM but at the same time I don’t want to antagonise anyone who could then object to any antennas I might want to put up in the garden.

Rotating the 6M Moxon around at the weekend during the contest as at least pointed me in the direction of one strong noise source. I am also convince that much of my problem is due to an evil PLT device in an adjacent property.

Following on from the weekend last night was the UKAC 50MHz contest and yet again I was troubled with noise leading to mostly local contacts.

I have been looking at some of the noise cancellers that are available from MFJ and others. I have heard conflicting options on their effectiveness but I am willing to try one if I can obtain one cheaply, or even home-brew one from the numerous designs available.

These devices work by using a second antenna which receives just the noise which is then mixed out of phase with the main antenna signal hence nullifying the noise. By all accounts they are tricky to use and often  need constant adjustment but may be my only viable solution at present.

No not a number station!

While on holiday last week I stumbled across some interesting transmissions on 11175kHz, my immediate reaction was some form of ‘number station’ however the messages finish with “Andrews Out” The American accent made me think immediately of Andrews Air Force base.

A bit of Internet research and I identified the transmissions as being part of the High Frequency Global Communications System (HF-GCS) and these messages being Emergency Action Messages (EAM) whilst apparently originally designed as part of the U.S. military’s strategic nuclear weapon command and control system, they must have other uses during peacetime (I hope)

There is an interesting post on the Milcom Monitoring Blog which has more details about what they may be.

Away from the noise

High up and a hillside in Cumbria at the moment, nine metre fiber glass fishing pole and 10 meters of wire, a ground spike and my FUNCube Dongle PRO+ and the laptop and what a revelation!
The entire HF spectrum spread out before me with little or no noise anywhere, signals booming in! and this was the view last night
As they say Location, Location, Location!
 

Pinneberg (DDK3) HF Weather Facsimile Transmissions

I have posted before about receiving weather and shipping facsimile transmissions on HF, for a couple of days I have been using the FCDP+ and WXSat to do some decoding, also been investigating some of the mysterious RTTY transmissions you also find.

Interestingly my previous experiment was using an Alinco Scanner with SSB capability, produced better results than using the FCDP+ and SDR#. not really sure why. It appears the some processing of the audio upsets WXSat, I have tried many settings and adjustments but the decodes haven’t been brilliant clear despite the signal being very strong and clear, many of the faxs have come in with odd ‘stepping’ where portions of the image go out of sync which I have corrected in PaintShop Pro.

Any way, here is a small selection of the images I’ve decoded from the Deutscher Wetterdienst, broadcast on 7880 kHz (DDK3) from Pinneberg in Germany,

 

WSPR using a FUNCube Dongle PRO+

For sometime I have been using my FUNCube Dongle Pro+ SDR as an HF receiver station for WSPR, so. I thought it was about time I posted something.

Introduction
By its very nature radio propagation isn’t totally predictable so someone transmitting can never know exactly where their signal will be received. There is whole science behind radio propagation prediction and amateur radio operators are always on the look out for openings or skip conditions for DX communications. To aid operators a number of propagation beacons exist, usually operating in CW mode transmitting their identification (call sign and location). Some of them use frequency shift keying and some transmit signals in digital modulation modes.

While invaluable operators have to actively receive and monitor these signals and what they really want to know is how their signal is getting out to the rest of the world. This is where the WSPR system comes into its own. The WSPR system uses a protocol which probes these potential propagation paths using low-power QRP transmissions.

WSPR (pronounced “whisper”) stands for “Weak Signal Propagation Reporter” and is a computer program that enables amateur radio stations to participate in a world-wide network of low power propagation beacons. The station transmits beacon signals and receives signals from other stations operating in the same amateur band. These stations then upload ‘spots’ that they receive in real time to a central website wsprnet.org enabling operators to find out where and how strongly they were received, and can view the propagation paths on a map.

It is also possible to operate a receive only station uploading ‘spots’ to the same website, all that is required is a receiver capable of receiving single side band transmissions and feeding the resultant audio into the WSPR program where it is processed. The WSPR program was written by Joe Taylor, K1JT.

These “whisper” signals are often barely audible but their presence can be detected by the WSPR program using signal processing. The WSPR signal uses frequency shift keying (FSK) with a very small shift and a very slow data rate. The signals bandwidth occupied is only about 6 Hz so many stations can operate within the 200Hz WSPR window without interference. WSPR transmissions are encoded to carry a station’s callsign, grid locator, and transmitter power in dBm. The program can decode signals with S/N as low as -28 dB in a 2500 Hz bandwidth.

Each transmission lasts for just under two minutes, and starts at the beginning of each even-numbered minute. Therefore it is vitally important that transmitters and receivers are synchronised, so one of the fundamental pre-requisites of success with WSPR is an accurately-set computer clock. This is achieved by using internet or GPS time synchronisation methods.

Setting Up

This diagram shows the set up I am using at the moment. I have a long-wire antenna connected to the FUNCube Dongle Pro+. I am using SDRSharp (SDR#) to operate the FCDP+ and the resulting audio output is then used as the input into the WSPR program.

I am using SDR# but any suitable SDR program could be used, I have used SDR-Radio and HDSDR but I have found the SDR# program uses less resources on my ageing PC.

Routing the sound output from one program to be the input into another can be problematic and depends on the soundcard and its driver, you might be lucky and have a ‘stereo-mix’ or ‘what-u-hear’ option to use the main sound card output as a recording input, or alternatively you will need to use something like virtual audio cable VAC.

Since the WSPR signal is very narrow band it is desirable that your receiver is accurately calibrated. Most SDR program that support the FUNCube Dongle PRO+ allow a correction setting so that the tuned signal is at the correct frequency, the use of beacons, repeaters, time signals or broadcast stations is an excellent method to set this correction if required.

You will need to download the WSPR program from http://www.physics.princeton.edu/pulsar/K1JT/ the current stable version is WSPR-2.11. The installation is straightforward and when you start the program a window will appear that looks like a command prompt, don’t close this window, it will give important debug messages if there problems. Then the main console window will open along with a window where you set the station parameters.

Don’t worry about the Callsign and Grid locator at the moment, the first thing to do is select the correct audio in source, the rest can be ignored as it relates to a transmitter and I am describing how to set up a receive only station.

Firstly slide the Tx fraction (%) to zero, since you won’t be transmitting and make sure the upload spots is unchecked at the moment, then select the appropriate band you wish to receive. Then set the appropriate dial frequencies in your SDR receiver program, this is shown in the window and your SDR program will need to operate in USB, with a bandwidth of 2500Hz.

The current WSPR dial frequencies are (MHz)
0.136, 0.4742, 1.8366, 3.5926, 5.2872, 7.0386, 10.1387, 14.0956, 18.1046, 21.0946, 24.9246, 28.1246, 50.293, 70.091,144.489

I suggest you turn off any AGC and any filtering in the receiver, uncheck the idle box in WSPR and then wait for the next ‘even’ minute at which point the program should show receiving, alter the sound level so the Rx Noise is ideally around 0dB, but it will work between -10dB and +10dB.

When the two minute interval is over a segment will appear in the waterfall in the top panel and the program will decode any WSPR transmissions received, you will see them as lines in the waterfall as the above image shows. Any successful decodes will appear in the bottom panel.

Once you have got it working, the next thing is to register on the WSPRnet.org website for a SWL callsign, mine is G-SWL10 you will also need to know your grid-locator, you can find this easily using http://f6fvy.free.fr/qthLocator/fullScreen.php

Once registered then putting the data into the station parameters and checking the upload spots will send your spots to the website database, where you can view your spots in the database and on a map, the map at the top shows my spots on one day this week on 20m, getting stations from Australia, the Far East and the US as well as Europe.

Some important things to note are ensure you computer clock is accurately set, if it is wrong you will be out of sync and decodes won’t happen and ensure you are tuned to the correct frequency as you have set the WSPR program otherwise spots will be reported for the wrong band.

It is a fascinating activity and even as just a receiver you are offering a valuable service to amateur operators.