Rendez-vous, clever use of AIS standards

Ben Ellison

Ben Ellison

Panbo editor, publisher & chief bottlewasher from 4/2005 until 8/2018, and now pleased to have Ben Stein as a very able publisher, webmaster, and editing colleague. Please don't regard him as an "expert"; he's getting quite old and thinks that "fadiddling fumble-putz" is a more accurate description.

7 Responses

  1. Fred Pot says:

    Here is how tender tracking and a “Pick-Me-Up” Alarm shows on Transas Navi-Sailor 3000 ECS-

  2. del says:

    If I read that picture correctly, the JetSki has sent a safety – text AIS message to ALL STATIONS?
    Surely it should have been an addressed message? Certainly, if I’d been anchored in the area, I wouldn’t have been happy to be receiving messages from some-one elses tender.

  3. Ben Ellison Ben Ellison says:

    Del, this is not real AIS! The messages are only being sent and received by a particular private network of Rendez-vous equipped vessels and tenders. No regular AIS receiver in the area can see the jet ski or the safety message. Rendez-vous use AIS messages but not AIS frequencies.

  4. caribelectronics says:

    The frequency used is a bit vague. The site mentions L-Band. I always took this to be in the 1 to 2 GHz region, but then it mentions VHF antennas and looking further mentions a license for 44.5MHz. this being in the low vhf Land Mobile allocation. Has Seacas bid on a block of channels in this range?
    Also what happens when the fleet moves to the Caribbean for the season. The license isn’t going to be valid in other jurisdictions.

  5. del says:

    ooops! Sorry Ben, I seem to have got a bit confused there – however, if I can get confused by the display, will others too?
    I’m a bit puzzled about the 44.5MHz frequency allocation – I’m not convinced it would be allowed in the UK.
    I have to admit a sneaking admiration for the kit though, it’s a neat idea to hijack someone else’s display for your own purposes, but the price seems extortionate – I’m sure I could knock something up in one of the UK’s license-exempt bands that would do the job – lower power and shorter range, I’ll grant you, but much, much cheaper!

  6. Fred Pot says:

    Rendez-vous customers are not required to obtain a license for the use of 44.5 MHz frequency in international waters.
    The Rendez-vous frequency range (low-band VHF, 40-50MHz) can not be secured from the FCC for US waters as an exclusive license because there is no auction nor bid. However, SeaCAS LLC’s partner, MeteorComm (, owns a co-primary non-exclusive license to use the 44.5 MHz band for both fixed base and mobile stations.
    It is not practical to register the frequency in every country that Rendez-vous customers may visit with their yacht. We rely on our customers to secure a mobile station 44.5 MHz frequency license for the countries they plan to visit. There are, however, a number of countries that do not require a license for a mobile station for this frequency.

  7. del says:

    looks like 44.5MHz is in the middle of a military band in Europe – probably unwise to use it over there unless you want a visit from the local marines / paras / SAS etc…..
    Now that data transmissions are allowed on the FRS band, wouldn’t that provide a cheaper (if range restricted) alternative carrier?

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