SDRplay RSPdx with go2MONITOR

Thanks to SDRplay, I was sent both their new RSPdx and older RSPduo SDRs at the end of January.

The main reason was to get them integrated into Procitec’s go2MONITOR and go2DECODE software, to increase the number of SDRs that the company’s products are compatible with.

This I’ve been successful in doing with the RSPdx – I’m still to unbox the RSPduo at this time of writing.

First of all though, I’ve been extremely pleased with the RSPdx in its own right. The SDRuno software works really well, is pretty easy to use – and it looks good too.

SDRuno running the RSPdx
The RSPdx also works with SDRConsole

The fact that you can have up to 10 MHz of bandwidth is brilliant, and it isn’t too bad on the CPU usage either – running at around 25% with 10 MHz bandwidth on my ancient PC. Used with SDRConsole you can cover a good number of frequencies at once, and can record them if necessary. Of course, you can do this with SDRuno too, but at the moment only IQ – you can’t record individual frequencies.

Saying that, I’ve seen the SDRuno Roadmap for future releases and not only will recording of individual frequencies be possible, a more advanced scheduler is to be included. This is something I feel SDRConsole – amazing though it is – is lacking when it comes to single frequency recording. There is also the issue with SDRConsole that you are limited to recording only 6 hours worth of wav file per frequency.

Anyway, I digress. Back to the RSPdx and go2MONITOR.

To get the SDRs to work correctly with any of the go2 products means creating a configuration file and adding a ExtIO DLL file to the software. This is reasonably easy to do once you get use to it and it enables a GUI to become active so that you can control the SDR through go2MONITOR.

One interesting aspect with the RSPdx GUI is that regardless of what you enter as some of the parameters in the configuration file, the ExtIO file overrides these. Effectively, I just left some of the data as found in a basic configuration template and let the GUI do all the work for me.

So, below are some of the results with today’s first test.

First of all I went into the VHF/UHF side of things and targeted the local TETRA networks. These were found easily and after messing around with the GUI, I was able to get go2MONITOR set up to nicely find all the emissions within the 1.6 MHz bandwidth I’d chosen to use

From there, all I had to do was to select one of the found emissions and let the software do its thing.

Next I moved on to HF where there’s a plethora of data to choose from to test out the SDR. There was quite a large storm going through at the time and my Wellbrook loop and coax feed were getting a bit of a bashing with some considerable interference being produced with the really strong gusts, as can be seen below – the interference between the two HFDL bursts is one such gust.

I’ve frequently mentioned the Results Viewer that’s part of go2MONITOR and with things such as HFDL and TETRA, that process data quickly from lots of signals, this part of the software comes into its own.

The image below is two minutes of HFDL monitoring. All the red blocks is received data that scrolled through the Channel window too quickly to read live. In the viewer you can select any of the signals and you’ll be shown the message as sent. In this case, it is one sent by an Open Skies Treaty observation flight OSY11F.

By looking at the Lat/Long and comparing it to the flight history from FlightAware and its location at 1313z it ties in nicely. This flight was carried out by the German Air Force A319 1503 specially kitted out to make these flights.

go2MONITOR has a basic map function within the Result Viewer function so if there’s any Lat/Long position within any message it will plot it – as shown below for OSY11F at 1313z.

Within the General tab of Result Viewer you can get all the parameters of the signal.

One final test that I carried out was how well everything coped with a bigger bandwidth. In HF I can use up to 3 MHz of bandwidth with the licence I have – going up to 10 MHz once into VHF/UHF. In HF then, I selected 3 MHz in the GUI and then ran an emissions search.

My PC is nearing the end of its life but it coped easily with the amount of data found despite only having 4 GB of RAM with a 3.6 GHz AMD processor – a new PC is in the pipeline that is going to give me much better processing power.

Despite having 3 MHz available, not everything was identified. Most of this was at the fringes of the bandwidth, but some of the weaker signals also failed. That doesn’t mean you can’t then process them further, you can, it’s just the Emissions scan hasn’t quite been able to ID them. Saying that, the software managed to ID things within 2.2 MHz of the 3 MHz bandwidth.

I picked one of the weaker signals to see how both the RSPdx and software coped and they did very well, pretty much decoding all of the CIS-50-50 messages that were coming through on 8678 kHz.

So, overall, pretty pleased with how the RSPdx works with go2MONITOR.

Once I get a better PC I’ll be able to test at bigger bandwidths but even with 3 MHz here I was able to achieve the same, if not better, results than I have with the considerably more expensive WinRadio G31 Excalibur I have been using previously (running with the G33 hack software).

Not that I’m likely to really use go2MONITOR at big bandwidths – 1.6 MHz is probably fine for me – but for Pro’s there’s no doubt that having these “cheaper” SDRs would make absolutely no difference over using an expensive one such as those in the WinRadio range. In all honesty, I don’t think I’ll be holding on to the WinRadio for much longer – I’m more likely to get another RSPdx to cover this area of my monitoring.

On its own, as an SDR, the RSPdx is worth the money I’d say. I like it just as much as I do the AirSpy HF+ Discovery – the only real difference I can see between these two SDRs is the max bandwidth available.

PROCITEC go2MONITOR overview

If you follow me on Twitter you’ll see that in the last month or so I’ve been sending out images of classification and decoder software go2MONITOR working with a number of my SDR’s.

go2MONITOR is part of the go2SIGNALS range of software solutions created by PROCITEC GmbH operating from Pforzheim in Germany, themselves part of the PLATH group. PLATH Group is the leading European-based solution provider for communication intelligence and electronic warfare (EW) with worldwide government customers. The group covers all aspects of signal interception and analysis split between a number of companies such as PROCITEC. EW, COMINT/SIGINT, Jamming and Decoding are just a small part of what the group specialises in.

go2MONITOR is advanced high-performance, automatic HF, VHF and UHF monitoring software capable of recording, SDR control, wideband and narrowband classification and multichannel signal decoding.

It isn’t for the faint hearted, but once you get used to using it, it really does make gathering information on networks extremely easy. And it decodes many modes other software can’t.

In a series of blogs I’m going to show you the capabilities of this amazing software, though I must stress now, it is aimed at Professional SIGINT gathering and it comes with a Professional price tag.

Saying that, it doesn’t mean it isn’t available to the non-professional. It is open to all and to cover this it comes in various versions starting with the Standard package progressing to a full Military package – which gives you the full range of HF, VHF and UHF classification and modem recognition decoders available, including PMR and SAT (Inmarsat AERO). The Standard version isn’t to be sniffed at, it still gives you an amazing range of decoders, though you could easily argue that many of these are available in other free – or near to free – decoding software like MultiPSK or Sorcerer. A full list of decoders available can be found here. Note, this list is broken down into the various packages and not all are available with the Standard option. Confirm what belongs to what if you’re thinking of purchasing.

Various signals within the Satellite L-band using an AirSpy R2 and SDR#

So what’s the difference in what go2MONITOR can do with other software available? That’s the idea of these blogs, to answer just that question. It will take quite a few blogs – mainly because there isn’t just one answer.

Here then, is a brief overview of what can be done, what SDR’s it works with – in fact, not just SDR’s but all receivers that can produce a recording – and any other things I can think of.

As, I’ve said then, it can decode pretty much any data signal out there. Obviously, some signals are encrypted so it wouldn’t fully decode unless you had the key, but you can get the encrypted messages. It can also classify voice signals, not just data. So, if you wanted to hunt out various voice networks, go2MONITOR can assist you in doing this.

Here is where it excels. Classification – and doing it very quickly.

Imagine being on your SDR (SDR1) and you can see a whole load of data signals on the waterfall/spectrum and you quickly want to know what they all are. With go2MONITOR operating another SDR (SDR2) you can dial in the centre frequency of the bandwidth shown on SDR1 into the go2MONITOR/SDR2 combo, click one button – Find Emissions – and within seconds the whole bandwidth has been analysed and every signal classified.

I’ll go back a step though here. You don’t need two SDR’s. One will do. SDR1 – as long as it is a compatible SDR – can be controlled through a GUI by go2MONITOR. The software includes a waterfall/spectrum display. Like all SDR software, these displays are fully adaptable to how you like to see the signals.

The previous L-band bandwidth but his time using go2MONITOR and the AirSpy R2 GUI, decoding INMARSAT 3-F2

Either way, you now have a list of every emission that go2MONITOR has received within that bandwidth. This list includes Modulation type, Frequency, Bandwidth, Symbol (Baud) rate and SNR. It also shows which SDR you have used for interception (useful if you’re using go2MONITOR with more than SDR at the same time, but also with other advanced features such as network control), and it also shows if the frequency is already stored within the frequency database – yes, you can create this too; or import ready made databases in a CSV format.

All the emissions within the bandwidth have been analysed and types ascertained.

Already then, you have built up a picture of what these signals are. One thing to note. If the signal type is not one of those included within the package you have, it will be classed as unknown. Example – a STANAG 4285 will show as unknown in the Standard and PMR/SAT package, but will be classified correctly in the MIL package.

OK, those of us that are looking at SDR’s all the time can pretty much tell what the signals are just by looking at them, so there’s no great advantage here is there? Except, now go2MONITOR has logged these in its database which can be searched through at a later date – handy if you’re looking for potential schedules for example.

However, the next step is where things get interesting. By putting one of these emissions into a “Channel” you can carry out an advanced classification, recognition and decode. You have multiple choices here, but I generally start off with a Classification. Whilst the software has already decided what the emission type is, by doing this it double checks just this one channel and produces a choice of decoders that it is likely to be.

go2MONITOR in Classification mode. Here it has calculated that the FSK emission received has a 50 Bd symbol rate with two tones with 859 Hz spacing. From this it has deduced it is likely to be one of four modems – one of which is ALE-400.

By using STANAG 4285 as an example, it will put this into the list of choices, but it may put other PSK signals there too. By clicking on another button, this puts the channel into Recognition mode and it reduces the hundreds of decoders down to just those in the classification list produced. The software then calculates which is the best decoder and starts to decode the signal.

If you think about STANAG 4285 in other software, you generally have to try all the various potential Baud rates – is it Long Interleaving? is it Short? etc etc. Well go2MONITOR does this automatically. It checks the alphabet and protocol and will decode it if known. More often than not it can’t calculate the alphabet, but every now and again it does and it will produce encrypted data – don’t forget, if it’s encrypted it won’t decrypt it without the correct key.

By continuing on the process from the Classification mode into the Recognition & Decode mode, here from another emission go2MONITOR has selected the CIS-50-50 modem and started to decode the message.

This further Recognition and Decoding is also stored in the database for later analysis, along with a recorded wav file for playback and deeper signal analysis.

Seriously, it is harder describing it in text than it is doing it so I’ve created a video that’s at the end of this blog.

I mentioned previously that the software works with receivers that aren’t SDR’s. That’s because, as long as you can create a wav file recording – Narrowband as it’s known in go2MONITOR – it can be analysed. There are things missing, the actual frequency for instance (though this can be typed into a text box so that you can then have the right information – this i’ll show in a later blog). Time stamps aren’t naturally there but again you can add these by telling the software to use the time the recording was started.

I’ve used recordings made on my Icom IC-R8500 as an example of this but it is literally the bandwidth of the mode used by the receiver that is shown on the go2MONITOR spectrogram.

You don’t actually need to own a receiver of your own. Use an online SDR such as a KiwiSDR, record the IQ as a wav file and play it back through go2MONITOR for analysis. I’m doing just that for a Jane’s Intelligence Review magazine article.

If you use SDRConsole, then you may have also tried the File Analyser function that I blogged about in August last year. The File Analyser in SDRC is excellent, there’s no doubt about it, but it has one drawback. Once you’ve carried out your recording you have to create a run through of the recording, making an XML file that effectively joins all the wav files up. If you’ve made a wide and long IQ recording this can take quite some time. With most of my overnight recordings – normally 7 hours long, with a 768 kHz bandwidth – this takes around 45 minutes to complete.

With go2MONITOR you can also record the bandwidth IQ data. With this you can do two things. Firstly you can run it through as a normal playback, classifying and decoding as you go. Secondly though, you can open the Results window which gives you a time based view of the whole recording allowing you to immediately see any transmissions. Unlike SDRC Analyser, the signals have already been classified, and more importantly, this is done straight away without any need to create an XML file first. The Results window will be covered in greater detail in a blog of its own.

Analysing a Wav file made using the IQ recording capabilities with go2MONITOR
Further analysis of a STANAG 4285 emission within the recording.

However, there are no decodings here. With just an IQ recording you need to play it back and run an emission search etc. There are some basic automation tasks available, such as setting up an emissions search every 10 seconds.

But, if you have the Automated Monitoring and Tasking package, you can also have the software automatically record, recognise and decode a single emission type – or all emissions types within the bandwidth, a set frequency, between two frequencies or any other parameters you may wish to set up.

The go2MONITOR results window of a IQ recording that has been set up to automatically run an emissions search every 10 seconds. The blue rectangles are every emission found. By running the mouse of them you can get basic information on each emission. Clicking on them brings further details that can be viewed in the tabbed area to the right.
The red rectangles are emissions that have also been Recognised and Decoded. By clicking on them the decoded data is shown in the tabbed area.

The list of SDR’s that can be used with go2MONITOR is pretty good, though due to the target audience, many of them are high end, “government/military” receivers. But, it does work with Perseus, SDRplay RSP1 & RSP2, RFSpace NetSDR and SDR-14, and of course AirSpy R2 – and now the AirSpy HF+ and AirSpy HF+ Discovery.

Supported receiver list:

ReceiverMax. Rx bandwidthSpectrum overviewScanRemark
AirSpy2 MHz  Experimental support
CommsAudit CA78515 MHz  VITA 49
Grintek GRX Lan1 MHz   
IZT R3xxx series20 MHzXXUp to 3 channels  spectrum
IZT R4000 (SignalSuite)1 MHz  1 channel only
Microtelecom PERSEUS800 kHz  Limited USB 3.0 compatibility
narda® NRA-3000 RX320 kHz   
narda® NRA-6000 RX320 kHz   
narda® IDA 2320 kHz   
narda® SignalShark®331020 MHz  VITA 49 support. Only 1 MHz and no receiver control at LINUX
PLATH SIR 211020 MHz  LINUX recommended. External receiver control only
PLATH SIR 21154×20 MHz  External receiver control only
PLATH SIR 511012 MHz  16×768 kHz subbands External receiver control only
PLATH SIR 5115Full HF  40×768 kHz subbands External receiver control only
R&S EB5005 MHzX No gain control available
R&S EM100 / PR100500 kHzXX 
R&S ESMD15 MHz  External receiver control only
RFSPACE NetSDR2 MHz   
RFSPACE SDR-14190 kHz   
RTLSDR/Noxon USB-sticks3.2 MHz  Experimental support. Continuous signal up to 2.4 MHz
SDRplay RSP1 & RSP26 MHz  Experimental support
ThinkRF R5500-4086.25 MHz  VITA 49
ThinkRF R5500-4276.25 MHz  VITA 49
ThinkRF WSA5000-408780 kHz  VITA 49
ThinkRF WSA5000-427780 kHz  VITA 49
WiNRADiO G31DDC800 kHz   
WiNRADiO G33DDC4 MHzX  
WiNRADiO G35DDC4 MHzX  
WiNRADiO G39DDC4 MHzX Up to 2 channels + spectrum
Generic VITA 49 receiver supportMax. receiver bandwidth  Can be configured in a wide range for different receiver types
Other generic “Winrad ExtIO” supported receiversMax. receiver bandwidth  Experimental support

As you can see, there is a huge difference in bandwidth capabilities for each receiver. I use my WinRadio G31DDC quite often with go2MONITOR, but the AirSpy HF+ Discovery (not listed as i’ve only just got it working) isn’t much worse with it’s full 610 kHz bandwidth.

When you think that the G31 has a much better operational bandwidth than 800 kHz when you use it on its own, it’s obvious which is better value if you were buying an SDR solely for using it with go2MONITOR. It is this kind of thing that many Government agencies are looking at when it comes to funding operations aimed at large scale monitoring.

That then is a very basic overview of go2MONITOR. The quick video and images have hopefully shown you a little of what is possible.

Outside of a Professional SIGINT operation, why would an amateur radio monitor need something like go2MONITOR? And would they pay the price?

I think they would. After all, most of us have spent a fair amount on radio monitoring over the years, so why not on software that would make their monitoring not only quicker and easier, but potentially open up new areas of monitoring.

Many of us specialise in certain monitoring areas – Russian military, particular the Navy and Strategic aviation for me for example. With go2MONITOR I have already used it to hunt out potential Russian Northern Fleet frequencies by running an automated 10 second CW emission scan overnight within a bandwidth block. By doing this, and then analysing data found in the results window, I was able to target certain frequencies to see what activity there was on subsequent nights.

Whilst there are other decoders available – some of which are plugins in software such as SDR#; some of which are free – it is the quickness and ease with which it can be done that makes go2MONITOR attractive. The big question is, would you pay for this?

SDR Console V3 analyser

The shack, finally operational after a few months off.

With the rebuild of my shack complete I’ve been able to start testing out all my radios, new connections etc.

The Mini-Circuits components all come well packaged in anti-static bags

A whole bundle of new cables from Mini-Circuits arrived last of all and have helped tidy up the back of the radio 19″ rack considerably. I’ve previously installed quite a few Mini-Circuits components, including 0.141″ diameter Hand-Flex interconnect cables, and so it was more of these that I opted for. The bonus with these cables is that they are hand formable meaning you can shape and bend them into pretty much any area that you want to. The 141 series (which I use) are capable of a 8mm bend radius, whilst the thinner 086 series can be bent to 6mm.

Being able to manipulate the cables certainly helps in tight spaces, and when you don’t want them to hang down

Previously I used hand-made cables with RG58U coax, but in order to have a 19″ rack that can slide out from under the desk, the cables needed to be longer than actually required. Because of this the cables would drop down into all the others attached to the PC and in some cases cause a little interference. With the Hand-Flex cables I’ve been able to use the same length of coax to allow me to move out the rack, but be able to bend them up and out of the way of the PC cables.

They’re also very good for the radios on the rack, being able to bend them and hold in place around the radios and other cables. They are near lossless too with a quoted insertion loss of 0.01 dB in the HF band to 0.55 dB at 18GHz. I normally run tests of the Mini-Circuit components when I receive them and find that the figures quoted are near spot on. I highly recommend these cables if you’re looking to upgrade your systems, and are available from the Mini-Circuits website, along with lots of other goodies that will tempt you.

Measurement of insertion loss of the Mini-Circuits ZF3RSC-542B-S+ Power Splitter/Combiner I also purchased as part of my plans for satellite communication monitoring. This is connected to the AirSpy SDR and takes feeds from two SatCom connections (currently deactivated) and a WinRadio AX-71C Discone Antenna. Mini-Circuits quote an insertion loss of around 19.5dB at 130 MHz which is confirmed here with a signal generated at -20dB being less than 1dB out at -40.48dB when passed through the combiner.

This image shows how the cables can be held in place without cable ties

The radio setup now includes two new SDR’s – an AirSpy HF+ and a standard AirSpy with the HF+ replacing the Enablia TitanPro. I’ve also reinstated my WinRadio G31DDC which had been in storage for a year or so. I really do like the TitanPro, and have put it into storage for the time being. The recording capabilities in particular are great with it being able to select 40 frequencies at once spread over numerous bandwidths, but I have had issues with the power supply – one being it caused interference. I attempted to make one of my own but it has a 6v(+/-1v)/2.5 Amp current requirement and no matter how many different methods of building my own supply using a 12v feed downgrading to 5, 6 or 7 volts, it just wouldn’t work in a stable manner. In the end it was easier to remove it and slot the G31DDC back in its place.

As it is, I’d forgotten how good the G31DDC is and I don’t really feel like I’m missing much thanks to the ability to use the other SDR’s with SDR Console V3 and it’s SDR Analyser.

The three 19″ racking units from Penn Elcom, along with all the shelves, have been very useful and certainly makes things easier when it comes to changing radios and connections over. I can just disconnect a few things and slide the whole unit out. I also obtained a 19″ Project box from them which I used as my main 12v switch unit. This is connected to two regulated desktop power supplies that act as master switches.

Although the SDR Console website page for the Analyser states it isn’t available yet, this is incorrect and it is downloaded with the latest version of the main programme.

If you’re a current user of V2 or have been in the past then you won’t notice much difference. You can have up to 24 parallel demodulators operating within the SDR’s bandwidth that you have chosen, all of which can run independent of each other in receive and record. You can also run each demodulator through a decoder such as MultiPSK independently and decode these in parallel with each other. This capability has taken that step towards those of the TitanPro, especially when being used with the Elad FDM-S2 that can provide a Maximum DDC bandwidth of 6144kHz’s.

Unfortunately, whilst you can schedule recordings of IQ data, you still can’t do this for individual channel recordings. This is a real shame as it would be a fantastic addition to the capabilities of SDR Console.

Getting back to the analyser though this does, in theory, cancel out the lack of channel recording scheduling.

When you record IQ data it is saved as WAV files, split into multiple ones depending on how long a recording you make . All of these files can be individually played back through the incorporated SDR Console player but even better is the use of the File Analyser.

With this you get a visual “image” of the complete recording, whereby after opening the analyser you get it to combine all the files into one XML file. For the image below I used the FDM-S2 with a selected bandwith of 768kHz centred on 4425kHz, hoping to catch calls to Russian Naval base Severomorsk in CW(RJD99) from ships operating in the region. I set the scheduler up to record from 0000z to 0700z which worked perfectly, giving me 78 files totalling 78GB – obviously, the bigger the bandwidth, the larger the total file size.

After clicking on New in the analyser and browsing to the relevant folder the WAV files are saved in, the analyser finds the first one and gives this as an option to open – it automatically adds the remaining WAV files and starts the process. This can take quite some time to extract, around 45 minutes for the example shown. But you only need to do this once because once it has finished you can save it as an XML file and open it at any time – in this case it was a 28MB XML file.

A note here – do not then delete the WAV files as the analyser still needs them.

As you can see, I was successful in locating calls to RJD99, and I have highlighted some of the others that I took a look at – this is just a screenshot of two hours out of the seven recorded.

All you then need to do is find any signal of interest, and after clicking on select and start in the top ribbon, click on the signal. This will then start playing the file from that location in the main SDR Console window. You don’t need to stay on that frequency, you can use the Console as if you were listening live and move around the frequency range you dictated in the bandwidth of the recording.

And, as it is basically a live screen you can do additional things such as record and use decoding software.

RJI92 calling RJD99 on 4416 kHz during playback of the Analyser

When using the Analyser I run this through a separate PC meaning SDR Console itself can carry on working on the main radio control PC. This is also handy if you’re away but have time to go through the IQ data using a laptop. Just copy over the original WAV files to a portable hard drive/memory stick and carry on as described above.

There are numerous other functions available for you to use with the main part of SDR Console, some I still haven’t had the chance to play with completely. I’m still exploring things such as the Signal History function which can store up to 48 hours of data. Here you can export data in CSV format to third-party programs such as QtiPlot. Signal history can also be used within the Analyser

This is useful as it can give you a quick overview into single frequency use, signal strengths, fading and such like. Definitely something I need to spend more time on.

It’s been a long time coming, but Version 3 of SDR Console has been well worth the wait.

Roland Proesch Radio Monitoring books 2017

Roland Proesch has announced that his latest books on Radio monitoring are now available at his website

Whilst Signal Analysis for Radio Monitoring remains a 2015 edition, the other three – Technical Handbook for Radio Monitoring HF, Technical Handbook for Radio Monitoring VHF/UHF and Frequency Handbook for Radio Monitoring HF – have all been updated to 2017.

There is also a new title – Technical Handbook for Satellite Monitoring – which is over 400 pages long and is aimed at those that are interested in satellite communication. The book is the usual high standard with figures and tables on satellite systems and the waveforms they use.

Because of the new title, all satellite information (nearly 100 pages) has been removed from the VHF/UHF book, but these have been replaced by new modes such as Radar, C4FM, DVB-T etc.

At the moment, there are no PDF examples available, but going to my previous blog at the last release can provide that information for now. I’ll update when they do become available.

I highly recommend these books and they are very well priced at 49Euros each plus postage. There’s also the usual bundle price discount if you want more than one – further information on the website.

But, if you don’t want to pay the postage and are heading to the HAM RADIO 2017 exhibition in Friedrichshafen, Germany on the 14 – 16th July, then Roland will have a stand there (A1-213). I’m sure he’ll be pleased to see you there – I wish I could attend, but I’ll probably have to wait the 5 years or so until I move to Bavaria myself.

The opening times and price list for tickets to the exhibition can be found here

Roland Proesch Radio Monitoring books 2015

Roland Proesch has recently updated his books on Radio monitoring.

Published in the last month or so, the four books are great additions to your bookshelves and priced at 49Euros each plus postage. He does do bundle offers if you’re thinking of buying more than one of the titles.

The titles are:
Technical Handbook for Radio Monitoring HF
Technical Handbook for Radio Monitoring VHF/UHF
Signal Analysis for Radio Monitoring
Frequency Handbook for Radio Monitoring HF

CoverTechnicalHandbook2013_1EI reviewed the 2013 edition of Radio Monitoring HF in March 2014.

Roland provided me with a PDF of the changes and additions to the books which you can find here:
New in Technical Handbooks

For more information on prices and examples from the books head over to Roland’s website

I will hopefully be reviewing three other radio monitoring books by three different authors in the next month:
Professioneller Kurzwellenfunk by Nils Schiffhauer
Spezial-Frequenzliste 2015/16 by Michael Marten
International Call Sign Handbook by Larry Van Horn

Monitoring NATO “Joint Warrior” Exercises

***This blog now contains some information regarding the current Joint Warrior 151 exercise***

Most of November I was away on holiday to the USA which is why there was a lack of a blog last month. This month I’m going to release one of my articles that was published in the July edition of The Spectrum Monitor. tsmcover

As I’ve previously mentioned the magazine is available in digital format, and can be read on all electronic readers. A yearly subscription is $24, which is a bargain bearing in the mind the monthly content produced, totalling over 1200 pages a year.

This version is slightly different to the one published in the magazine as it contains some extra content.

Monitoring NATO “Joint Warrior” Exercises

Twice a year the UK hosts Exercise Joint Warrior(JW), planned by the Joint Tactical Exercise Planning Staff (JTEPS) based at Headquarters Northwood, about 5 miles north of Heathrow Airport. JTEPS is a joint organisation parented by both HQ Air Command & Navy Command (NC HQ).

The Official Mission of the Exercise is to:
Provide a joint, multi-threat environment in which UK, NATO and Allied units and their staffs may undertake collective training and pre-deployment training in tactical formations in preparation for employment in a Combined Joint Task Force

The number of participants is normally quite large, with up to 30 naval vessels, both surface and sub-surface, taking part. The number of aircraft taking part is substantially larger with sometimes up to 100 being involved. These include Maritime Patrol Aircraft(MPA), Fast Jets, Command and Control (C2), Intelligence Surveillance Target Acquisition and Reconnaissance (ISTAR), Transport, Air to Air Refuellers and Helicopters

As well as Air and Sea assets, there are Land based Air Defence units along with Paratroops, Army and Marines. The number of personnel involved is in the thousands.

JW normally involves forces from major European countries as well as the USA and Canada. Other countries such as New Zealand, Australia and Brazil have taken part in recent years.

This French Navy Aquitaine Class Destroyer "FS Aquitaine" (D650) is seen arriving at Her Majesty's Naval Base Clyde, also known as Faslane. The French are huge users of HF, in particular they use STANAG4258, RTTY and HF-ALE. The STANAG and RTTY is normally encrypted but you can sometimes get callsign information from the messages. They also use USB, especially the Transports, AWACS and Maritime Patrol Aircraft

This French Navy Aquitaine Class Destroyer “FS Aquitaine” (D650) is seen arriving at Her Majesty’s Naval Base Clyde, also known as Faslane. The French are huge users of HF, in particular they use STANAG4258, RTTY and HF-ALE. The STANAG and RTTY is normally encrypted but you can sometimes get callsign information from the messages. They also use USB, especially the Transports, AWACS and Maritime Patrol Aircraft

The exercises can cover the whole of the UK, but most of it takes place in Scotland and its surrounding waters. There are certain areas in other parts of the UK that are used, for example the Spadeadam Electronic Warfare Training Range (West of Newcastle, England) and Fast Jet Areas over the North Sea (for Air to Air combat). But it is the limited population of the North West of Scotland, along with quiet air and sea traffic, plus access to both deep and shallow waters, which allows almost total freedom for the participants. There are also numerous weapons ranges some of which include areas designed specifically for Naval Gun Support (NGS) and Close Air Support (CAS) – Cape Wrath on the North Western tip being the main one.

Joint Warrior 141 (JW141) took place between the 31st of March and the 11th of April, 2014. The week prior to the main start of the exercise there was a general build-up of forces as the scenario heads to conflict between fictional countries, starting with Amphibious Forces congregating at West Freugh and Luce Bay off South West Scotland.

"SSN Missouri", a USN Virginia Class SSN, leaving Faslane in 2013.

“SSN Missouri”, a USN Virginia Class SSN, leaving Faslane in 2013.

Meanwhile, the main naval forces from the different participating countries generally arrive at Naval Base Clyde, more commonly known as Faslane. The base is close to Glasgow, and is the home of to the majority of the UK Submarine Fleet, including Vanguard Class SSBNs and Astute Class SSN hunter-killer submarines. It is also the home of the mine countermeasures fleet. Faslane gets regular visitors from various Naval forces throughout the year, a not too uncommon site being USN Virginia Class SSNs that pass through for supplies and crew rest.

JW141 hosted the following countries sea and air elements:

The Netherlands and Belgium also provided Marine forces, as well as the Netherlands and USA providing Forward Air Controllers (FAC).

The UK of course provided the largest amount of participants with numerous ground, Paratroop and Marine regiments, Air Defence and FACs taking part, along with sea and air elements consisting of:

I’m pretty sure there would have been at least one UK Submarine involved though I do not know the details of this. The Astute Class are still in their infancy and so would have been ideally chosen to take part.

Despite my previous statement that it is quiet in Scotland when it comes to sea and air traffic, it isn’t desolate. There is still a large amount of flights into the major cities of Scotland, it is just it is quieter than in Southern England . There are numerous daily warnings sent out to civil aircrews about possible military activity and this works in the other direction too, with the military crews getting briefings on airways and areas to avoid.

Sea warnings aren’t left out either, in particular for the large fishing industry that exists off the West coast of Scotland. For this, JTEPS produces a document that is published on the Government website that provides information on Submarine, Minewarfare, live firing and denial of GPS training for the exercise. This can be a useful document should you be interested in following what is happening during the exercise as it tends to have a program of events and maps.

***I have updated the page to show the document for the current JW151 exercise and it can be found here. There are also daily SUBFACT and GUNFACTS broadcast as part of the NAVTEX warnings

Radio Communications

What JW does bring with all this action is radio communications. In fact, one of the main aims of the exercise is to establish common procedures between forces that are likely to work together for real in a combat area.

All types of communication methods are used, including the old fashioned “flag” and “flashlight Morse code” between ships. In the majority though, it is of course radio that is used to its fullest. And, it is the full spectrum that is used from VLF all the way up to SATCOM, most of which is easily received by monitors around the UK and further when it’s HF that is being used.

As well as voice comms, data takes a large part, especially RTTY, Link 11, Link 16 and STANAG4285. All of this is normally encrypted but if there is a non NATO country taking part then sometimes data is sent in the clear, especially RTTY.

Because of the large expanse of operating areas, HF is used extensively. Over the last few years I’ve built up a record of frequencies used that have been monitored by myself and others also interested in the JW exercises.

A Lockheed Orion CP-140 of the Royal Canadian Air Force, 140116, lines up to depart Lossiemouth during an intense sandstorm in 2013. Just visible in the background is the parking area for the Maritime Patrol Aircraft (MPAs) that take part in Joint Warrior. The usual mix includes USN P-3 and RCAF CP-140 Orions, but has included French, German, Norwegian and Brazilian Navy MPAs in recent years

A Lockheed Orion CP-140 of the Royal Canadian Air Force, 140116, lines up to depart Lossiemouth during an intense sandstorm in 2013. Just visible in the background is the parking area for the Maritime Patrol Aircraft (MPAs) that take part in Joint Warrior. The usual mix includes USN P-3 and RCAF CP-140 Orions, but has included French, German, Norwegian and Brazilian Navy MPAs in recent years

The Maritime Patrol Aircraft normally operate out of RAF Lossiemouth and arrive a few days before the exercise begins. Once StartEx has been announced there is at least one MPA airborne at any one time until the exercise ends, quite often though there are two airborne. Mission lengths are around 6 hours including transits and they consist of Anti-Surface Warfare (ASuW) and Anti-Submarine Warfare (ASW). The aircraft are designated a trigraph callsign such as A8X as allocated to the USN P8A of VP-5 on the 2nd of April, and these are changed daily. One thing of note with the NATO MPA element of the exercise is that the aircraft are not allocated their callsigns by the exercise staff but from NATO itself, as they are on call to deal with any real-world scenario that may take place. Should there be any non-NATO MPAs in the exercise then these are allocated their callsigns as normal by JTEPS.

When the aircraft get airborne they normally call Northwood, callsign MKL, on HF with a departure message. This is followed by an on-station message and then hourly sitreps until off-station and then landing. They would also call for any information or if they themselves have something to pass such as enemy sightings. The primary frequency used on HF is 6697kHz. As well as using HF the MPAs will communicate on UHF with any vessels in their operating area, though this well out of range of my location so I don’t normally hear this.

RTTY (or RATT) is the primary method of passing the information, though this quite often seems to fail. It is quite amusing sometimes listening to an MPA set up a RTTY message by voice with MKL, which then fails repeatedly, sometimes taking 15 to 20 minutes of attempts. They then give up and send by voice a 30 second message – I sometimes wonder why they bother, especially when it’s something as basic as a departure message.

I normally set up my Icom IC-R8500 and Winradio Excalibur right at the beginning of the exercise to monitor the HF frequencies, in particular the MKL primary 6697 kHz. Along with this I ensure my Bearcat UBC800XLT is up to date with all the correct VHF/UHF frequencies, and that my Bearcat UBC3500XLT mirrors it for when I’m mobile

Talking of going mobile, my usual routine is to head to the Faslane area to catch the arriving and departing ships. Normally, the ships will arrive on the Thursday and Friday before the start of the full exercise. Due to the large amount of ships involved they are given arrival slot times, much the same as aircraft do at airports. This is so that the local Harbour masters, Police escorts, Tugs and Pilots are not stretched to the limit with everything arriving at once. The ships use the standard Marine VHF Channels to communicate with the Pilots etc (Channels 12, 14, 16 and 73). This is usually quite interesting to listen to, in particular this year with USN participation – for instance USS Cole was very twitchy about pleasure craft in the area, even asking the Police escort to intercept a suspicious vessel heading straight for them. The calm response of “Errrr, that’s your Tug and Pilot” was quite funny. On the Sunday, the reverse takes place with all the ships leaving, this time slightly more grouped in small flotillas.

Arleigh Burke class Destroyer USS Ross (DDG 71) about to pass RFA Lyme Bay (L3007) of the UK Royal Fleet Auxiliary

Arleigh Burke class Destroyer USS Ross (DDG 71) about to pass RFA Lyme Bay (L3007) of the UK Royal Fleet Auxiliary

Over the weekend, RFA Lyme Bay and RFA Orangeleaf had anchored a few miles short of Faslane at an area near to Cloch Lighthouse (where I based myself). I was able to receive both these ships on UHF frequencies though I was unable to clearly tie-up the callsigns used by the ships. Just before 0700z, numerous coded messages were sent between the callsigns 8DE and 7GO. These continued until 0800z when 8DE calls “Anchors away”. There was the sound of horns across the bay and RFA Lyme Bay moves off, turning a tight 180 degrees to head south. RFA Orangeleaf follows behind. From this I concluded that 8DE was probably Lyme Bay.

When I’m waiting for things to happen, and scanning with the UBC3500XLT, I’m also using the Close-Call facility of the radio for the UHF band to see if I catch anything else. This time it didn’t work, but another monitor in Northern Ireland was a lot luckier and was able to add a few frequencies to the growing list:

There were plenty of calls on these frequencies, but the usual line of sight problem arises with UHF and the ships would quickly disappear out of my range. But it didn’t matter as HF is used extensively because of this very problem for the ships themselves.

Monitoring from the Shack

With the Icom on 6697 kHz and the UBC800XLT scanning the hundreds of VHF/UHF frequencies, I’d use the Excalibur to search through for the ships HF communications. Like the VHF/UHF ones, there are frequencies that are used every year and one’s that aren’t. But once you’ve found the regular ones you can pretty well catch most of the action. Along with a small group of others that also monitor JW we were able to build up a good picture of what was going on.

It became clear quite quickly that 4706 kHz was being used for Ship Air Defence calls. Over the two weeks this task would be carried out by various units, and by all military methods – Land, Sea and Air. The Land element would be carried out by the RAF Air Defence Unit, based at RAF Boulmer (usual callsign HOTSPUR). The Air element would be from a E3 AWACS (though not that often) and the Sea element would be carried out by a ship. By the callsigns used it sounds like the task is split into three during a 24 hour period, with maybe Boulmer doing 2 slots and a ship the other; or whatever the aim of that days scenarios that have been planned by JTEPS.

The calls would look something like this taken from my logs:
(1132z)
J0T this is G1T
New friendly ML500
Position MKQN0105
Hdg 287
New friendly ML500

(1133z)
Update friendly ML500
Pos MKPN5606
Hdg 287
Spd 166kts
Strength1
C height 19
Update friendly ML500

This is decoded as:
ML500 = allocated track ident by radar operator
MKQN0105 = grid reference
Hdg 287 = Heading 287 degrees
Spd 166kts = speed of track
Strength 1 = number of aircraft in formation
C height 19 = Mode-C radar height

These calls are made very quickly, every 30 seconds to a minute, and actually get quite hard to write down. The training carried out from these calls is very important and not only assist the radar operators but also things like the defence systems on board the ships.

Cobham Aviation Falcon 20 G-FRAW taxies for take-off from RAF Lossiemouth during Joint Warrior 12-2 in 2012. The photo clearly shows all the additional pods these aircraft carry for replicating different aircraft, radars and weaponry

Cobham Aviation Falcon 20 G-FRAW taxies for take-off from RAF Lossiemouth during Joint Warrior 12-2 in 2012. The photo clearly shows all the additional pods these aircraft carry for replicating different aircraft, radars and weaponry

The exercise uses the Civil fleet of Falcon 20 aircraft of Cobham Aviation Services to replicate different aircraft. To do this they use towed targets that can be programmed to have the Radar Cross Section of aircraft such as Sukhoi Su-27or Su-35 Flankers to give the radar operators a true feel of what they would possibly see for real. The pods also replicate missiles as fired by the “enemy” aircraft and can be programmed as such, a “favourite” being Exocet as these have been used in anger against Royal Navy ships, sinking a few in the Falklands Conflict in the early 80’s. The Falcon 20’s can fly very low over the sea up to 300KIAS, and believe me they fly low, I flew in one year’s ago. Other equipment carried can give immediate information of simulated hits or misses by the ships Air Defence weapons, much like ACMI pods (Aircraft Combat Manoeuvring Instrumentation) carried by aircraft.

Sometimes the Falcons also fly with Royal Navy Hawk fast jets, operated by 736 Naval Air Squadron. 736NAS used to be known as FRADU (Fleet Requirements and Aircraft Direction Unit) and the task of these Hawks is to simulate low flying missiles against ships. As the Hawks can fly faster than the Falcons this gives a better simulation to the ship’s crew to help them learn how to combat the threat, or at least reduce the possible damage caused should the missile get through. The Hawks can also carry out the same task as the Falcon 20s replicating enemy aircraft.

The Falcon 20s can also carry out other tasks such as Electronic Warfare by jamming the radars and radios and using chaff and flares. They are very capable aircraft and used continually by the UK, not just in exercises such as Joint Warrior.

By far, the best Maritime Air Defence platform currently at sea is the Daring Class Type 45 Destroyer of the Royal Navy. In JW141 it was HMS Dragon of this class that took part. The Daring class destroyers are fitted with a Marconi Type 1046 Air/Surface search radar which functions in the D-band; and a Surveillance/Fire Control E/F-band Type 1045 (Sampson) Multifunction radar made by BAe Systems. These radars combined can give a 400km,/360° coverage, linking in to the Principle Anti-Air Missile System (PAAMS) which provides target cueing, anti-jamming, radar de-clutter and other functions necessary to protect itself and any other ships in the fleet. For protection the primary weapon is a Vertical Launch System (VLS) capable of holding 48 missiles in single missile cells. These hold either Aster15 or Aster30 S/A missiles with ranges of 15nm and 30nm respectively, with Aster30 reported to have a range of up 65nm. The VLS is capable of having a mix mode, where any combination of the two missiles can be held, the usual mix being 32 Aster 30s and 16 Aster15s. Future developments of the Aster30 include an anti-Ballistic Missile version with a range far exceeding that currently available, with reports of it having a range of 540nm, with a further version exceeding 1200nm.

© 2014 Tony Roper.No usage permitted without authors permission

Göteborg Class Corvette Sundsvall (K24) of the Swedish Navy in a Joint Warrior exercise from April 2013. Every exercise has different participants from different countries, which allows for greater training and learning of techniques used by the differing Navies of the World

It would take pages to go through everything you can hear on HF during JW. It’s a 24/7 activity as the exercise runs day and night, 7 days a week including weekends. You can normally hear the Gunnery ranges at Cape Wrath as ships take it in turns to simulate attacking shoreline targets, normally given instructions by FACs. There’s general radio chat with resupplies, tasking of ship helicopters, and as previously mentioned, the setting up of RTTY and STANAG4285. Most of the general calls were on 4915.5 kHz which seemed to be the Primary Ship HF frequency. Plenty of callsigns were heard every day, though in the majority they couldn’t be tied up as intended.

HF frequencies used over the years that have been logged by myself and others:

Air to Air

© 2014 Tony Roper.No usage permitted without authors permission

Royal Air Force Tornado ZA404/013 in full afterburner as it departs RAF Lossiemouth in April 2013 on a Joint Warrior mission. Being this close to the runway is very noisy and very hot. Within 6 months, this Tornado had been transferred to RAF Leeming and scrapped, being used for spare parts for the remaining fleet of Tornados

The Air element of the exercise takes place for most of the two weeks with a multitude of tasks being carried out by the Fighters, Transports, Tankers and electronic warfare aircraft. Again, to go through the full amount would take pages of information but I’m sure you can imagine how busy the airwaves can be with such a large amount of aircraft taking part.

In the majority, the Fighters use Tactical Air Direction (TAD) frequencies (most people incorrectly call them Tactical Air Designator frequencies). These are “real time” frequencies used by the Air Defence Network in the UK and there are hundreds of them. The actual frequency is never said on the air with the TAD number (channel number) passed instead – TAD156 for instance. To confuse things even more, in JW the TADS are given other codenames, normally colours (as are the HF frequencies in fact) and these are said over the air too. Of course, if you have the TAD frequencies this isn’t a problem as you can tie the colour up. As it is, there isn’t a definitive list of frequencies officially available, though some are known.

As you can imagine, the chat on the frequencies is busy as fighters intercept others fighters, or transports and such like. It’s interesting listening and hasn’t changed much from when I was in the RAF. Though, I’ve got to say it isn’t as busy as it used to be, mainly down to target datalinking between aircraft. The datalinking means that less information is passed over the radios either between aircraft in a formation, or from E3 AWACS for instance. Data is also transmitted from the ground from the Air Defence networks or mobile forces.

The Hercules transports were kept busy most of the exercise with plenty of paradrops, both human and freight. And there were plenty of Helicopters around from ships, as well as RAF and Army elements. Most of this is carried out on common inter-squadron frequencies, and those of the main RAF Area Control based at Swanwick in Hampshire (Southern England, and also home to the Civil London Area Control Centre).

This year the exercise ended with an “Apocalypse Now” scenario with a mass Helicopter and Hercules assault on a disused airfield, RAF Kinloss. This is far out of my range being about 240 miles away so I wasn’t able to monitor it, but I did catch the Helicopters travelling back and forth from there to West Freugh where a mobile base had been established, West Freugh being about 40 miles to the south of my QTH.

Overall, the exercise normally brings a good build up in radio communications for UK listeners, especially HF. But unfortunately, HF isn’t that popular within the Military listeners of the UK where the majority listen to VHF/UHF frequencies. The funny thing is, they’re probably missing the vast part of the exercise.

Three Tornados of the RAF carry out final checks lined up on the runway during Joint Warrior 12-2 in October 2012. Tornados operate with two crew, Pilot and Navigator/Weapons Officer, and have been in full service in the RAF since 1982 but are now in their final years. They have served the RAF well over this time, taking part in all combat Operations since their initial introduction into service, including Operation Desert Storm where they flew as low as 50 feet at over 500mph (something they do every day over Scotland). Their crews are probably the best Low-Level combat pilots in the World

Three Tornados of the RAF carry out final checks lined up on the runway during Joint Warrior 12-2 in October 2012. Tornados operate with two crew, Pilot and Navigator/Weapons Officer, and have been in full service in the RAF since 1982 but are now in their final years. They have served the RAF well over this time, taking part in all combat Operations since their initial introduction into service, including Operation Desert Storm where they flew as low as 50 feet at over 500mph (something they do every day over Scotland). Their crews are probably the best Low-Level combat pilots in the World

DIY Canon EOS 5D Camera fix

Canon Eos5D(mk1) DIY fix

There I was on a harbour tour of Portsmouth, snapping away at the (large) amount of RN ships docked there at the moment, when my 5D made an awful clunking, grating sound and stopped taking images. Looking through the viewfinder gave me nothing but darkness. After a brief panic, I took the lens off and sitting in it was what looked like the shutter mechanism from the camera. Luckily I also had my 50D with me, so I was able to continue with what I was doing, but as soon as the time became available I took another look at the 5D

As it was, it turned out it wasn’t the full mechanism but just the mirror that had come unstuck, so the thought of huge amounts of money flying on to my credit card stopped as I thought it would be a reasonably cheap fix. I did wonder if the previous weeks wet shoot of HMS Duncan may have been the cause. It had been a wet day, but the camera hadn’t got seriously soaked as I protected it. It was, however, also quite humid, so I think the two weather patterns and the clunking process that shutters have to go through combined to unstick the mirror a little. This final shoot was enough to let the mirror lose it’s grip completely

5D_001

Back home a few days later and I investigated the price of getting the mirror put back on. I was shocked to find that the price for this repair was ridiculous, prices between $250 and $500 were being quoted by people with the same problem in the USA (I couldn’t find a price in the UK). This was crazy, and I seriously thought that at that price I may as well look for another 5D

But then I thought, well I may as well see if a bit of superglue to the back of the mirror will work. So I Googled to see if others had tried this, and they had, and it had worked

So this is this is the process I carried out to make the DIY fix.

1. Obviously, make sure you’re in a clean area, with as little dust as possible

2. On the back of the mirror is a small black piece of thin plastic, take this away. There’s no need to remember or mark what way round it goes as this is obvious by the holes

3. Cut the end off a cotton-bud

Remove the black plastic and cut off the end of a cotton-bud

Remove the black plastic and cut off the end of a cotton-bud

4. Get the superglue and squeeze some out onto a piece of paper, card or plastic – whatever you have available really. DO NOT squeeze superglue directly onto the small pads on the back of the mirror, we all know that superglue has a mind of its own and is hard to control in small amounts

5. Take the cut end of the cotton-bud, scoop up a small amount of glue and dab it onto one of the small pads on the mirror – you don’t need too much. Repeat this for the other three pads, but do it fairly quickly before the glue can dry

6. Return the black plastic to back of the mirror

7. Look at the shutter mechanism of the 5D and note the correct way round the mirror should go by the position of the indents for the pads

8. Gently place the mirror on the shutter mechanism, applying only a small amount of pressure

Mirror fixed back in place. Now let the glue dry followed by a clean

Mirror fixed back in place – now let the glue dry followed by a clean

9. Close up the camera with the lens cap and leave it for a few hours to dry properly

10. After a few hours, test to make sure the camera works correctly and the mirror stays in place

11. Give the mirror a clean as its bound to have some fingerprints on it

This took me about 5 minutes, and cost the price of one cotton bud and a tube of superglue – both of which I had already

Cross Country Wireless HF/VHF/UHF Multicoupler

With the total rebuild of the radio-shack looming I’d been investigating on a Multicoupler for my VHF/UHF radios. My homebuilt antenna connected to my Bearcat UBC-800XLT is far better than the bought Vertical Antenna that is connected to my Icom IC-R8500 so I wanted to remove the vertical antenna (using the co-ax for a homebuilt AIS antenna I’ve been testing in a different location) and use the Bearcat antenna on multiple radios

I’d found a few Multicouplers that suited, but after a discussion on MilCom about different ones, and a recommendation on one of my choices, I decided to go for the Cross Country Wireless HF/VHF/UHF Multicoupler multicoupler

I wasn’t the only one as I know at least one other member of MilCom made the same choice

There was a slight delay in delivery as Chris, the owner of CCW, was away on holiday. But as the units are made to order this wasn’t a problem to me at all

When the Multicoupler arrived I put it to use immediately and was very pleased with the results. It does have to be powered by a 12V adaptor and I had one of these spare, it can go down to 7V I believe, but either way power is required or you’ll get nothing. I ran the Multicoupler with the two radios, and even added my UBC-3500XLT to it too, with no loss at all. Very happy indeed.

However, a problem did arise. For some reason, reception would drop off over time. A quick chat with Chris bought about the probability that it was the power unit as he tests everything before sending out. Using another power supply the problem was fixed – initially. After a few days the same happened again, with great reception at first but then a drop. The power supplies I used were of the same make, so I queried it with Chris and he told me of a supply they have available that doesn’t seem to have any problems at all. So I purchased this too, and a few days later it arrived

Since then I’ve had no problems at all, and I am very pleased with it. I have only used it for VHF/UHF, not HF, so I can’t give any critique on its performance in this area

Temporary placement of the Multicoupler for testing

Temporary placement of the Multicoupler for testing

The HF/VHF/UHF Multicoupler is priced at £119.95 plus shipping (£8 in the UK I believe)
The 12V power supply is £20 including postage to the UK

Further details and specifications are available on the CCW website