An updated AIS system

Back in March I blogged about my AIS system, in particular about the LNA4ALL and how it coped with the low signal reception of my homemade antenna.

Things went really well until one day the reception dropped out completely.

A quick test of the system showed that something had gone wrong with one of the pieces of equipment though at the time I was unsure whether it was the antenna, the LNA or the NASA Engine AIS decoder.

As I was due to go away for a short while I decided to tell all the relevant websites that I feed (IHS AISLive, MarineTraffic and VesselFinder) that my system would be offline until further notice due to a technical fault, and that as soon as I’d worked out the issue that I’d get it fixed and back online.

The guys at MarineTraffic were very quick in getting in contact with me and offered to help with a new decoder as long as I didn’t mind being a beta tester for the equipment and some of their new software. I was very happy to agree to their offer.

The decoder they organised for me was a new Comar Systems SLR350ni Intelligent AIS Decoder and it arrived with me about ten days after I agreed to their offer.

The main thing that really appealed to me about this decoder was the fact that it links directly to your home network either by WiFi or hardwired using RJ45 Ethernet cable. This meant that I could install the decoder remotely, nearer to the antenna and out of my radio shack, but have full control of it from my main PC. The decoder itself is interfaced to a Raspberry Pi™ 3 computer, comes with aforementioned WiFi and Ethernet connectivity, 4 USB ports and an HDMI connector for a monitor display. It can be used in any AIS setup and is a dual channelled parallel receiver.

Installation was simple. Within 15 minutes the decoder was connected to my home-made antenna and we were receiving data – and at a much faster rate than the NASA due to the dual channel capability.

The MarineTraffic part of the agreement included some new software that they are testing, which includes the capability of sending received raw AIS data to five feeds such as AISLive. Any of these decoders obtained using MarineTraffic come with their host settings hardwired in so any data received through it is automatically sent to them – you don’t have to do anything to send data to MarineTraffic, just attach an antenna, connect it to your network and switch it on – that’s it.

In the new software there is a page where you can add other host iP addresses and port details. Doing this means a couple of things:

1 – You no longer need to use other software such as ShipPlotter or Neal Arundale’s NmeaRouter/AisDecoder software to forward on the data.
2 – You don’t actually need a PC connected directly to the Comar decoder.

The second point is interesting as it means you no longer need to have a PC running 24/7 to feed any of the AIS data to whichever sites you want. This is a bonus if you currently switch off your computers when you go on holiday or are away from home for a while. It still means you can provide the data whilst you are away.

Personally I have the following set up:
MarineTraffic (hardwired)
AISLive (iP host)
VesselFinder (iP host)
ShipPlotter (internal network address)
AIS Decoder (internal network address)

Using the ShipPlotter software still means I can get a better picture of what I am receiving, range of reception etc.; whilst using the AIS Decoder software means I can look at any of the messages sent in greater detail.

I have to say that I am very impressed so far, and highly recommend the Comar decoder. It is available from numerous online shops, but if you are going to feed MarineTraffic you may as well get it from their site, currently priced at €379.00. Doing this means it already comes pre-programmed to send to MarineTraffic.

A new antenna too

I had gotten round to testing all the equipment to see what the cause of the original loss of reception was and it turned out to be the LNA4ALL. This was a shame as I had new objectives for the LNA with regards to the reception of weather satellites so it means I’ll have to get a new one. Luckily I don’t need to replace the whole thing, just the circuit board, so it will be much cheaper – but a pain none the less, especially if I have the same issues with UK Customs that I had previously. The likely cause of the failure was an Electrostatic Discharge of some sort or other. There had been some Lightning storms nearby over the previous days and it could well have been this that had done it – strange though as my equipment is very well protected from this happening. The area I live in is prone to power surges and power cuts – the joys of living in a remote area in Scotland, still backwards in many things the rest of the UK take for granted.

With the loss of the LNA, this drastically reduced the range of my home-made antenna and so I decided it was time to buy a new one. I’d toyed with building a better one but in the end I just couldn’t be bothered and so I went for a Metz AIS antenna, bought from the Salty John website. Great service from them meant it arrived within 48 hours and so when it came to installing the Comar decoder I also rigged up the antenna in the loft space next to my home-made one at the same time.

If I have one complaint about the Metz, it’s that it doesn’t come with any form of protection for the co-ax connection area. This is especially strange as it is designed specifically for boats and would therefore be exposed to wet/salty conditions all the time. Add to that that the threaded area is over an inch long, much longer than what you would get with a UHF connector, this makes it a weak area for the lifetime of the antenna. If you were to install it outside (which is the general recommendation for AIS reception) then you would need to cover it in self-amalgamating tape and check it regularly to ensure it is still working. Not perfect if you need to climb up on the roof of your property.

One other option would be to use the tightening nuts supplied to fix some plastic or aluminium tubing around the connection, but again this is some extra hassle which could have been remedied by Metz themselves.

As it is, I seem to be getting great coverage from the Metz from it’s position in the loft, though I may still add a LNA4ALL to boost it even more.

With the antennas side by side I was able to run some quick comparisons between the two. The images below show the Spectrum analysis using my Rigol gear.

From the images you can see that with my messing around of the home-made antenna I had over trimmed it to be tuned to 180MHz rather than the required 162MHz. At 162MHz it measured in at 9.3dB which wasn’t even worth calculating the VSWR, whilst at 180MHz its VSWR was 1.23:1

In comparison the Metz antenna, which is a half-wave whip antenna, came in nicely at 83.6MHz with a measurement of 30.15dB/VSWR 1.07:1. Metz communications specify less than 1.2:1 VSWR so this is spot on.

With the new set up things have definitely improved. I also ran a quick test using AISDecoder to see how many messages the two antennas fed to the Comar, be it in a very basic manner of waiting till there was some ships being picked up, running the software with one antenna for a minute, noting how many messages were received and then swapping to the other antenna for the same length of time. In theory it is a reasonable test as the ships won’t have travelled far in that time, but not 100% perfect. Regardless, the Metz was able to pick up 19 messages in its minute test, whilst my home-made antenna only managed three! The test was carried out in less than five minutes.

In conclusion, whilst it has been a pain to lose the LNA4ALL, it has turned out better in the end for my AIS station. Statistically my data feed has improved no end for AISLive and MarineTraffic; and having gone away twice now since installation I have still been able to provide 24/7 coverage where I would normally have switched the whole system off.

Area coverage provided to MarineTraffic since the new installation. Fitting a LNA4ALL in the future should make this even better.

ShipPlotter example with the new installation. The bold plots are being received by my station and show 4673 messages received by 1032z. The image below shows the same but at 1753z and a message number of 28135. This averages out at about 52 messages a minute, though it was a busy time with lots of fishing boats in the area.

NOTES:

Following a couple of questions regarding the Comar decoder I’d like to add that it doesn’t have to be connected to the Internet or a Network to work. It can be used “locally” using the USB connections direct to a PC.

Also, you do not NEED to feed MarineTraffic if you don’t want to. If you don’t want to do this then buy a unit from another supplier which won’t have the files installed.

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Fighting Ships 2017/2018

In the last month or so the latest edition of Jane’s Fighting Ships has been released. It’s available from the IHS online shop for the usual eye-watering price of £984.

One thing to note is that older editions of the yearbook are also available on the IHS website at much cheaper prices.

This is the last edition that Commodore Stephen Saunders RN will be the chief editor of, as he has decided to retire from the role after 17 years. Having been a contributor of JFS for the last five of those years it will be sad to see him go.

From now on there will be a multi-team of editors that will compile both the yearbook and the on-line version. I will be remaining a contributor, and will hopefully be getting more involved than I am already.

There could well be complications regarding contributing data and photographs and I suggest that if you do either of these then to contact the team at IHS as soon as possible. There is a strong likelihood that contracts will need to drawn up with regards to copyright usage of whatever you send in. The email address for the yearbook is JanesFightingShips@ihsmarkit.com

In the meantime, I wish Stephen all the best in his retirement – he’s done a great job editing the yearbook over the last 17 years.

Fred T. Jane

Today, the 8th March 2016, marks the centenary of the death of Fred T. Jane, the founder of Jane’s Fighting Ships and all the off-shoots of products that now exist under his name. He was 50 years old.

Fred was discovered on the morning of the 8th March 1916 “dead in bed at his residence in Clarence Parade [Portsmouth]” and “had been attended during the past week or so by Dr Cole-Baker on account of an attack of influenza, and had also complained of heart trouble, but his sudden death came as a great shock”.

FTJ_002He lived quite an amazing life during those 50 years, too much for me to cover here, but luckily a book was written about him by Richard Brooks, published in 1997. The book is still available today, easily found on Amazon for instance, and is titled Fred T. Jane – An eccentric Visionary (From Ironclad Ships To 21st Century Information Solutions) – and it is a great read.

Not only did Fred invent Fighting Ships and All the Worlds Aircraft, he was one of the first people to have a motor car in the UK (including racing them), he was one of the first private pilots (though not very good going by all the crashes he had), he was a member of Parliament, he was a writer of Science Fiction (at the same time as H.G. Wells was writing on the very same subjects) and a very successful artist. It was the artistry and writing that got him into creating Fighting Ships, even though there were other successful books in existence at that time covering the same subject matter. It was his line drawings and silhouettes that made Fighting Ships stand out from the rest, and it is why the books are still in existence to this day whilst the others have dwindled into the past.

As well as writing and illustrating his own Science Fiction, he created artwork for other writers, including this for the book "Olga Romanoff" by George Griffith in 1893.

As well as writing and illustrating his own Science Fiction, he created artwork for other writers, including this for the book Olga Romanoff by George Griffith in 1893.

Taken from the 1932 edition of "Fighting Ships", the earliest in my collection.

Taken from the 1932 edition of Fighting Ships, the earliest in my collection.

The early Fighting Ships books, the first of which was printed in 1898, went into extraordinary detail. These included the same details as is found in todays editions – weapons, crew numbers, engine types, speed etc., but also down to such details of the thickness of hulls in the various areas of each ship. The details on guns and armoured hulls were given comparative identifiers to show that a certain type of gun was capable of piercing a certain type of armoured hull. It was from this that the use of the books became manuals in “WarGames”.

Four metres of "Fighting Ships". Nearly every edition from 1946 to 1995, plus the earliest I have from 1932

Four metres of Fighting Ships. Nearly every edition from 1946 to 1995, plus the earliest I have from 1932

Now, these WarGamers weren’t just “nerds” sitting around at home, these were Naval Officers who used the information for training and strategy building, although the game was available to the public too. Prices at the time ranged from 4 guineas to £40 (around £4,400 in todays money), though the top end product “contained practically all the warships in the world” and was used primarily by various navies, including the Japanese Navy. The “games” came with model ships as part of the boxed set.

The early editions were in Landscape format, with different "standards" available - the "top end" versions were leather bound.

The early editions were in Landscape format, with different “standards” available – the “top end” versions were leather bound.

Though the Royal Navy was very slow in taking up the game, the Russian Navy were extremely interested in it and invited Fred to St. Petersburg in 1899 where he met Tsar Nicholas II. Grand Duke Alexander Mikhailovich even wrote the preface to the 1899 edition of Fighting Ships, the Duke being the Tsars brother-in-law. Fighting Ships isn’t even officially sold to anyone in Russia anymore.

"The British Battle Fleet" first edition from 1912

The British Battle Fleet first edition from 1912

Thanks to this trip, Fred was able to publish an off-shoot book titled The Imperial Russian Navy which led further to The British Battle Fleet – a book I have in my possession in its first edition format. It is thought that to this day, no one else outside of Russia has had such access to their fleets. Fred became good friends with members of both the Russian and Japanese Navies, something that caused him grief later on during the Russo-Japanese War of 1904-05 where he lost friends on both sides.

Fred died on his own, though he had an estranged wife and a daughter, but his legacy still lives on today. Ironically, the house he died in was bombed by the Germans in the Second World War, but flats that were built there in its place has a plaque commemorating his name. FS15-16

I’m very proud to have had my photographs printed in recent editions of Fighting Ships and I enjoy very much the research I do on the Russian Navy that I then forward on to the yearbooks current editor, Commodore Stephen Saunders RN. He is just the eighth editor in the 118 years of publication.

For more information on Fred T. Jane, please look up the previously mentioned book by Richard Brooks – you won’t be disappointed.

Fighting Ships 2015/2016

This years edition of Jane’s Fighting Ships, edited by Commodore Stephen Saunders RN, is now available to purchase from IHS for a wallet crunching £825.

There’s around 50 of my images in this edition, along with data I provide on the Russian Navy. FS15-16

Whilst this is good news, there’s also bad news regarding IHS Jane’s publications.

For the last few years I’ve been selling the older versions of the yearbooks that IHS have been unable to sell. Being two years old the books were discounted heavily to me to bring them within the prices enthusiasts would pay for a book.

Unfortunately, this is no longer the case. I shall be updating my sales page in the near future with information on how you can go about purchasing these older books, along with prices etc.

I expect though, that I shall be closing down my direct sales.