You read it correct..



dAISY is an AIS receiver.

What is AIS?


I’ve meant to give AIS monitoring a try for years but being honest, the cost of the USB receivers put me off if I found the coverage would be poor.

I was just googling this and that one evening when I came across a forum and read through all pages on the development stages of the dAISy. I thought this sounds a way of entering the dedicated RX market although I already have the facilities to use a data cable and 9600 rates on a radio needed to decode AIS but as I use that radio for my HF data work, a separate wee box would do nicely.

I read all I could about her and decided to bite the bullet and get one sent over from the US.



I knew the capabilities of reception, knowing that it would not be as sensitive as a dedicated box. It allowed me into the world of AIS rx’ing at very reasonable price.

I bought the little beauty at the Tindie store and I exchanged emails with Adrian who is the developer, excellent quick helpful replies!!

I tracked the package and it soon arrived, I’d downloaded a trial copy of Shipplotter so I could run dAISY and see whether I would keep or possibly upgrade at some point.

The unit was ‘plug and play’ on Windows 10, support is there for other versions, and after a short set-up, I fired up the programme, one or two settings later, I clicked on the green circle. Instantly I was seeing ‘messages’ being logged, I could see the positions of each ship on the map (you do have to calibrate a map when first running Shipplotter but there is ‘How to do this’ online.

I knew dAISy had limits of 8 to 12 miles due to the internals used but that would be enough to me, I did mail Adrian who pointed me to a user who has coverage of up to 59 miles, this user is on the Columbia River which uses an AIS repeater system. My best so far is 16 miles N to Loch Goil, I’m located at just under 500 ft ASL but there is higher ground between me and parts of the river and lochs. My limit seems to 16 m N, 9 miles W and 8 miles E, local geography comes into play. I’m sure if are suitably placed with a clear view, much better distances could be achieved.

Clyde Estuary


The 21 day trial period of Shipplotter was coming to an end, decision time.

I bought it although you can use other freebie progs such as AISMon, OpenCPN, AIS Decoder among others. I’ll be keeping an eye on the further development of these programmes.

Clyde Estuary

Clyde Estuary

I also did some experimenting with my SDR dongle which I can use straight audio to pnAIS which uses voice to report each message and shows you on a separate open window ships info.

I’ve stuck with dAISY..as it is KISS.

I run an old Toshiba laptop and watch the ship movements on the river and am presently ‘following’ a ship making its way down the river from just under the Erskine bridge, my limit to the E.


I’ve now begun uploading my AIS captures to the Shipplotter server and am receiving other sharers input, I have just expanded my map some to ‘catch’ the boats 15 to 20 miles away. It gives me much more info than before, my own RX’ed ships are still distinguishable from the others.

I also incorporated my AIS info into aprs.fi which I use when out and about, I have recently been uploading my weather station output 24/7 under my ham radio callsign, I’m weighing up running both the AIS and WX but will decide at a later date.


I’m not going to explain all the techy details, see below.


dAISy specs.

  • Single channel receiver
  • Receiving on channel A (161.975 MHz) and B (162.025 MHz)
  • Quickly alternates between both channels through frequency hopping (<10ms)
  • Sensitivity down to -100 dBm
  • Very low power consumption, less than 100mW in receive mode (<20mA at 5V)
  • No drivers required for Windows 10, Mac OS X and Linux (driver available for older versions of Windows)
  • 38400 baud serial over USB
  • Optional TTL serial output (3.3V, requires soldering)
  • Message output in industry standard NMEA format (AIVDM)
  • Small size: 63 x 44 x 23 mm
  • Sturdy aluminum enclosure
  • BNC connector for 50 Ohm VHF antenna (antenna not included)
  • Mini-USB connector for data and power (USB cable included)
  • Made in the USA

dAISy is © Adrian Studer…

Thanks go to Adrian for developing a cheap entry point into the world of AIS and you can buy one HERE

Further information on ongoing development HERE

Shipplotter HERE

All links and info are given in good faith.

© Google, Shipplotter, dAISy, Terrametrics.



About gm7something

64, married, three kids......overweight, unfit, folically challenged, need I go on ?
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