Masthead mobile internet/phone antennas

[gspeak]

We have a RFI antenna mounted on the pushpit which is plugged into a Telstra 4G USB modem that is plugged into a Dovado Pro WiFi router below. We get great reception in places like Lady Musgrave, the Percy’s, Island Head creek etc. The Dovado is 12 volt so is hard wired direct to house system.

[Snowpetrel]

Thanks GSpeak, that sounds like a simple and effective system. Maybe masthead mount isn't needed... Getting range out there is impressive. When I last sailed out their we got nothing on our phones as far as I recall.

[gspeak]

I must stress that I am talking about our setup for mobile data only. Phone/Voice is not our aim as wherever we have internet then we have Email/WhatsApp/FaceTime/Skype/TV via streaming etc. We know when we’re not going to have anything at all (not often) then plan around it beforehand.

[Snowpetrel]

^^ thats fine by me, I don't tend to be much of a talker. It's just so useful offshore around the coast to be able to get internet data these days.

[gspeak]

Check out telcoantennas

Antennas & Dovado wifi routers.There are many other wifi routers but Dovado has a great name & is easy to set up & they update their modem drivers often & does auto firmware updates etc.

We have the Pro as we need the extra ethernet & USB ports. We have our Morningstar Tristar MPPT solar controller plugged in via ethernet & can see live data & data logs of its performance. Also have a NAS plugged into extra USB port for TimeMachine backups etc.

All on 12 volt of course. We continue to run our business as permanent live aboards on our Lagoon 380.

The Dovado Tiny is very capable & cheaper with less ports.

Happy to answer any questions.

Dave

[Snowpetrel]

Sounds good. The presure is off a bit if I don't really need to mount it at the masthead. I can afford to wait until I need it. I am still a year or two off any serious sailing, but while the mast is out I don't want to miss out on a good opportunity. Thanks

[DevoDave]

I have done most of a circumnavigation of Oz and have a masthead mobile antenna with the 18m drop using LMR400 cable. This cable is damn expensive, very thick, and was a bugger to run. At the other end of the cable is an Ericsson W35. (If I was buying now there would be a Cel-fi device... they are the gear to buy now)

Similar comments to a couple of earlier posts, the importance of an extremely low loss cable is the critical issue. At cell frequencies, any significant length of normal cable will degrade the signal significantly.

I cannot stress this enough!

With this setup, I have had uninterrupted service (Telstra) for most of the journey. Crossing the Bight, the middle of the Gulf of Carpenteria, and parts of the NT and WA where there were no community celltowers, and the southwest of Tassie were the only spots where I did not have service. I even received a call midway across Bass Straight in the middle of reasonably big blow.

LMR400.

[Snowpetrel]

^^ Thanks Dave, those cell fi units look interestiing.
https://www.cel-fi.com.au/how_celfi_works.html

Not sure how it would work in a marine environment?

Edit: there is a car and marine version
https://www.cel-fi.com.au/cel_fi_go_repeater.html

Your setup sounds very good. Getting signal mid bass strait would be pretty handy. I'll have to price out some of that LMR400 coax or maybe the cell-fi would be cheaper? Any idea on costs

Cheers.

[DevoDave]

Powertec.com.au sell a marine version of Cel-fi. Probably targeted towards larger vessels but I have seen one on a 48 foot cat.

As long as you have low loss cable you can use any device.... or even a simple pigtail to plug straight into your mobile.

[Snowpetrel]

This LMR400 kit doesnt look too expensive. At $165 https://boostersformobiles.com.au/co...=4344063361055

I wonder if it is tinned, and if the end connectors work with vHF as well. Probably easier to run it up the mast without fittings and add them after. But for now there is a fair bit of work to do just to get the mast back in the boat!

[swampbush]

Originally Posted by Snowpetrel

^^ Thanks Dave, those cell fi units look interestiing.
https://www.cel-fi.com.au/how_celfi_works.html

Not sure how it would work in a marine environment?

Edit: there is a car and marine version
https://www.cel-fi.com.au/cel_fi_go_repeater.html

Your setup sounds very good. Getting signal mid bass strait would be pretty handy. I'll have to price out some of that LMR400 coax or maybe the cell-fi would be cheaper? Any idea on costs

Cheers.

The celfi units are great but as long as you have data now most modern phones allow voice over wifi. Most modems have antenna connections, so plug the modem into the antenna and makes calls over wifi. Use whatsapp instead of sms. The cell fi units are specific to telstra or optus, so you cant change providers without spening another $1000.

[Wotname]

Originally Posted by Snowpetrel

This LMR400 kit doesnt look too expensive. At $165 https://boostersformobiles.com.au/co...=4344063361055

I wonder if it is tinned, and if the end connectors work with vHF as well. Probably easier to run it up the mast without fittings and add them after. But for now there is a fair bit of work to do just to get the mast back in the boat!

There are many versions of LMR400; the devil is in the detail. Some (much??) of it is not suitable for marine (especially mast) installations. Some issues with some versions are large bend radius, not flexible enough, easily crushed. Some potential problems can be overcome with careful installation and using flexible tails etc. I strongly advise getting professional advice before committing to this style of coax (I guess I would advise that with any coax ).

Dockhead and ka4wja have posted about some of the issues in the past and I concur with most of their thoughts about LMR400.

Some versions could be suitable.

Don't worry about the end fittings, any connector you are likely to be using can be sourced for LMR400 and connectors are better fitted in situ rather than pre-made (IME). In your instance, there are suitably qualified techs with correct tooling nearby to assist .

If you plan on the single coax and swapping antennas, then I suggest using N type connectors and choosing antennas with N type terminals.

[Snowpetrel]

Thanks Wottie, I will definately take you up on your kind offer. This stuff is all double dutch to me...

[Wotname]

Originally Posted by Snowpetrel

....... This stuff is all double dutch to me...

Here you go, help you sleep at night...
http://www.ti.com/lit/ml/slap127/slap127.pdf

[Wotname]

Just found this, I think one can do better but as an off the shelf item, it seems OK.
https://www.youtube.com/watch?time_c...&v=TWg2_M_SbfE

The trade off is always height vs coax length vs cost