June 2020 - Article Error - Sateliite v HF radio

[Captain Crunch]

Good evening,

On Page 43 of the June 2020 edition of YM, the new Icom IC-SAT100 was described as a mobile phone under the Satellite Communications paragraph. This device is neither a mobile phones or even a satellite telephone in the normal sense.

The ICOM IC-SAT100 works using the Iridium PTT service (PTT = Push to Talk). This device cannot be used to make telephone calls or send text messages to landlines, mobile phones or other satellite phones. It works like VHF. The user pushes the PTT button, and all other compatible handsets that are joined to the same network will hear what has been said.

For this to work, the handset needs to be joined to a network called a talk group. Talk groups are private and fees are payable. The amount paid is related to the size of the geographical area covered. In addition to the month fee for the talk group, there is also a monthly fee per handset to access the network.

Whilst the Iridium PTT system is not suited for general public communications, it can be a useful and reliable mode of communication for operation that need a reliable form of private communication. Its suitable for race organisers for example.

My advise to ocean yachtsmen is that the ICOM IC-SAT100 is not the device for you. A better solution is to go for any other Iridium, Inmarsat or Thuraya technology that allows you to make standard voice calls or access internet data (or both).

NOTE: Iridium and Inmarsat offers global cover. Thuraya covers parts or the EU, Africa, Middle East and Asia only.

 

[Laser310]

interesting product though..., i hadn't seen it.

It seems there is a new version of the Iridium 9575 handset - the Iridium Extreme PTT - that has all the regular features of the older 9575, plus the PTT feature.

I could see this being useful for emergency communication between competitors in an ocean race - given that nobody has HF anymore, and a big complaint against satphones is they lack the one-to-many ability of HF. Kind of like a VHF, but for greater distances.

 

[Captain Crunch]

interesting product though..., i hadn't seen it.

It seems there is a new version of the Iridium 9575 handset - the Iridium Extreme PTT - that has all the regular features of the older 9575, plus the PTT feature.

I could see this being useful for emergency communication between competitors in an ocean race - given that nobody has HF anymore, and a big complaint against satphones is they lack the one-to-many ability of HF. Kind of like a VHF, but for greater distances.

Yes - Absolutely agree that this would be a useful technology for race organisers. The thing to keep in mind is that whilst Iridium has global cover, the real actual cover available is defined by the person or organisation that owns the talk group. An online portal is used to set up the cover area. The larger the cover area, the more expensive it is. In a race, management can easily use a smaller area and move it with the fleet of boats.

I work in the Humanitarian sector and in charge of our technology teams who deploy to various disasters. Under my management, I have all the radios and satellite telephones. I have been looking at the PTT options for some time as I see this as a replacement for the HF radios we use in remote areas. A few years ago I conducted trials of the Iridium Extreme (PTT) version. Whilst I am a big fan of the extreme handset, this opinion does not extend when I operate the handset in PTT Mode. The problem is that in PTT mode, the earpiece operates at high volume like a normal VHF radio. As the earpiece was not designed to work as a speaker, the sound was highly distorted. The work around is to attach a speaker/mic external handset.

I also trialed the Icom in Febuary this year. I was really impressed with its build and sound quality. We have just ordered 11 handsets which are now on the way to Liberia for our remote teams.

 

[Laser310]

for an ocean race, i think it only makes sense if all the competitors have it.., and they will rebel against any mandate for this.

 

[awol]

for an ocean race, i think it only makes sense if all the competitors have it.., and they will rebel against any mandate for this.

Since January 2020 OSR Cat3 and above mandates
"an AIS Transponder which either:
a) shares the masthead VHF antenna via a low loss AIS antenna splitter; or
b) has a dedicated AIS antenna not less than 38 cm (15”) in length mounted with its base not less than 3 m (10’) above the Waterline and co-axial feeder cable with not more than 40% power loss "
Apart from arguing about exactly what is an AIS transponder - the answer seems to be a Class B transceiver - there has been no rebellion .
... and no, I don't comply 'cos my AIS aerial is mounted on the pushpit.

 

[Laser310]

this is a fair bit more expensive than AIS

AIS is very useful inshore.., and most boats that do offshore races already have AIS and they want to have AIS anyway

Boats I race on already have fairly expensive sat devices -a perfectly functional iridium handset, fleet broad band, VSAT, and so on - depending on the race, we have been required to have a sat phone for offshore racing for some time now.

any PTT requirement would mean that all that existing sat com gear is obsolete - that's what people will object to

 

[[70521]]

My advise to ocean yachtsmen is that the ICOM IC-SAT100 is not the device for you. A better solution is to go for any other Iridium, Inmarsat or Thuraya technology that allows you to make standard voice calls or access internet data (or both).

Hello and welcome

Are you qualified to advise people on such matters? Asking for a friend.

 

[Laser310]

Hello and welcome

Are you qualified to advise people on such matters? Asking for a friend.

for what it's worth.., I agree with him.

It would almost certainly be a mistake to purchase that unit unless you already have a fully functioning satellite phone/data system on your boat, and intend to keep it.

It's capabilities are very limited, are targeted at a very specific use, and do not extend to address the needs of the vast majority of sailors that wish to buy sat phones.

put simply: it doesn't do what they want to do..

 

[Bilgediver]

Hello and welcome

Are you qualified to advise people on such matters? Asking for a friend.

No need for qualifications. The Icom publicity blurb makes it quite clear that is is only suitable for specific group use.

 

[lw395]

for an ocean race, i think it only makes sense if all the competitors have it.., and they will rebel against any mandate for this.

I would think that a group PTT system might be a fair option for certain races, like those where one organisation owns all the boats.
I would guess that the group would be all the boats plus at least one ashore.

 

[Laser310]

really where it would be valuable is coordinating a rescue effort

realistically though, on the major ocean races, usually at least a few boats within VHF range of anyone, so i don't think the added security is worth the expense - at least now. maybe eventually a lot of handsets will include this feature, and the data plans will as well.

races that would benefit the most tend to be low-budget long-distance races, were there are few competitors, so they get spread out - the are not going to get this.

then you have vendee, volovo, and so on.., where the expense is trivial - but they are already in pretty regular communication with the race office. The volvo boats were monitored 24/7.

 

[[70521]]

No need for qualifications. The Icom publicity blurb makes it quite clear that is is only suitable for specific group use.

I just thought it was odd that somebody with a total of two posts, calling himself captain, and speaking as if an authority on a topic that we all understood, hence I was interested to hear about his background and why he felt the need to point out the bleeding obvious. But hey, chill, its only been 51 days since my last haircut and not being able to feel salt in the wind is having a detrimental effect.

 

[RobbieW]

I just thought it was odd that somebody with a total of two posts, calling himself captain, and speaking as if an authority on a topic that we all understood, hence I was interested to hear about his background and why he felt the need to point out the bleeding obvious. But hey, chill, its only been 51 days since my last haircut and not being able to feel salt in the wind is having a detrimental effect.

The OP gives a reasonably comprehensive answer in post 3. I think I have reasonable grasp of comms technologies but hadnt come across the PTT feature of the Iridium network, so I've found the discussion useful

 

[newtothis]

I just thought it was odd that somebody with a total of two posts, calling himself captain, and speaking as if an authority on a topic that we all understood, hence I was interested to hear about his background and why he felt the need to point out the bleeding obvious. But hey, chill, its only been 51 days since my last haircut and not being able to feel salt in the wind is having a detrimental effect.

I'd hazard a guess that the "captain" is not of the nautical sense, but an homage to John Draper, legendary 60s phone hacker, who used a whistle from a Cap'n Crunch cereal box to fake dial tones, and used the cereal brand as his online handle.
Given that, I'd imagine the OP probably is an authority on this topic,