Re: Mobile communications - 4G, WiFi


Paul Dowd and Sharon Brown
 

David,

 

In my experiences, in the Med 3/4G has worked well, in the Caribbean wifi has given me a better service. If you do use wifi be aware that systems that use a USBL cable to connect to a receiver integrated in the base of an antenna, such as Redbox, will not work very well if the cable is too long. I have used Digital Yacht (coax to the antenna) and Bullet, also known as Webcatcher, and currently in use (RJ45 cable with PoE to the antenna) without problems but had no end of trouble with Redbox (USBL). I have never used a directional antenna. When I bought the Webcatcher in Martinique (Diginav in Le Marin) it came with a choice of three antenna sizes, and I took the middle one which was a good compromise between vertical beam width and range. Note that in rolly bays vertical beam width does become significant. This system has not failed me in four years. Note that my priority has always been reliability, then cost.

 

Cheers,

Paul

S/Y Ya Fohi - Amel 54 #98

 

From: main@AmelYachtOwners.groups.io <main@AmelYachtOwners.groups.io> On Behalf Of David Crisp
Sent: 23 January 2020 07:25
To: main@AmelYachtOwners.groups.io
Subject: Re: [AmelYachtOwners] Mobile communications - 4G, WiFi

 

Since my original post I have read the responses (thank you all) and trawled the web.  There maybe others like me treading this path so I thought I’d share what I’ve learned/concluded so far.  One caveat, I’m a very modestly technically literate sailor, definitely not an RF, electronics or networking engineer. If I have made any silly errors please let me know, I’m keen to learn.

 

I’m not currently aboard so doing much of my layout thinking from memory.

 

To recap the requirement: I’m going to be cruising the Mediterranean and want to be able to access the internet. Ideally, I’d like to able to get weather forecasts whilst coastal sailing offshore/between islands, subject to the limits of 4G coverage of course. Budget: Conscious that cheapest isn’t always the best, I’d rather spend a bit more to get performance and quality than save a bit but regret it later.

 

 

(a) Prioritise 4G/LTE over Wi-Fi. A number of people have commented how Wi-Fi systems are often overloaded and slow, that 4G provides better data rates.

 

(b) It’s more cost effective (and satisfying) to assemble my own system than buying a turnkey setup (e.g. DigitalYacht, Red Box etc). I’ve found a couple of exceptions to this but they have a major downside with the SIM card being badly located – more on this later.

 

(c) Antenna

Use an external omni-directional antenna (vs. one down below).

 

Keep the cable run from antenna to modem/router as short as possible to minimise losses. Mounting the antenna high up is less important than keeping the cable run short. This leads me to thinking possible locations for the antenna are: mizzen spreader / aft rail or arch / between the backstays. Least attractive is on top of the mizzen mast due to the distance.

 

Use LMR-400 coax cable if the cable routing permits.

 

To get the benefit of 4G/LTE a MIMO antenna is needed. The Poynting OMNI-402 gets very good reviews on build quality  but it’s expensive at UK£290 (https://www.solwise.co.uk/4g-antenna-omni-402). One or two articles seem to challenge the benefit of a MIMO antenna https://seabits.com/poynting-omni-antenna-testing/ and https://novaroundbritain.home.blog/2019/10/18/internet/ and maybe a simpler OMNI-291 (UK£144) SISO antenna would deliver pretty much the same performance (still very good build quality) but at half the cost.

 

I have looked at a couple of integrated solutions such as the WEBBOAT 4G LITE from Glomex (€609) https://shop.glomex.it/en/webboat-coastal-internet/660-it1104-webboat-coastal-internet-4g-wi-fi.html and Solwise QuSpot omni LTE/4G (UK£452) https://www.solwise.co.uk/WI-AX11S which have the antenna, 4G modem (SIM card) and router all integrated into the antenna dome. These look cost effective, eliminate antenna cable losses and look simpler to install however it means regular access to the SIM card is a problem if installed on a spreader or between the backstays. Why the need for SIM card access? From what I can understand there’s a need to either return to the UK with my UK SIM card every few months to maintain the EU roaming or to buy a SIM card in each country as the EU roaming expires. Either way regular access to the SIM card is needed.

 

(d) 4G Modem/Router

The Teltonika RUT 240 (UK£124) https://www.solwise.co.uk/4g-routers-rut240.html looks like it’ll do the job. The LAN port means I can one day connect an NMEA bridge should I want to. One could spend a little more and get the Teltonika  950 (UK£166) https://www.solwise.co.uk/4g-routers-rut950.html as this has 3 LAN ports which leave room for more expansion.

 

Location of the router will be determined by where the antenna cable enters from above (I’m not aboard at present). I’m assuming with a GRP structure WiFi propagation from the pilot berth or aft cabin (likely router locations) throughout the boat should be adequate, certainly to the saloon and aft cabin.

 

(e) WiFi

Assuming marina/cafe provided WiFi data capacity will be usually poor I may still buy a WL-Patriot-DB (UK£87) https://www.solwise.co.uk/wireless-Patriot-DB to at least try in each location. This would plug into the WAN port of the router. It’s powered over ethernet which simplifies matters. I’d either locate it somewhere inside or stick it outside temporarily via a porthole maybe.  It’s IP65 rated so if its outside in a rain shower it should be okay, but I’d be reluctant to mount it permanently outside.

 

 

Comments and suggestions encouraged.

--
David Crisp
SV Wilna Grace
Amel 54 #58


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Cheers
Paul
Ya Fohi - Amel 54 #98

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