HAM / SSB / SAT Phone

[conachair]

Originally Posted by SoonerSailor

There wont be any difference in the images between Pactor and Satphone, they are both just digital pipelines.

One difference, cost of airtime.

[Paul Elliott]

Originally Posted by lsoltero

The answer is yes...

Baud is a measure of performance. It means bits per second.

Sorry, the answer is no:

Baud rate refers to the number of symbols per second. The raw bit rate depends on the baud rate and the number of bits encoded by each symbol. QPSK (Quadrature Phase Shift Keying) is an example of a modulation method that encodes two bits per symbol. In QPSK the bit rate is double the baud rate.

There are many modulation schemes that use variations in phase, amplitude, and frequency to carry many bits per symbol. Look at the Shannon theorem to see how many bits can be pushed through a noisy band-limited channel, but bitrate and baudrate are definitely different things.

In spite of this terminology disagreement, there is no question that XGate and other optimized protocols / applications can deliver a dramatically improved bitrate. As I've said before, I've done the tests myself and as a result am a satisfied XGate customer.

[s/v Jedi]

Originally Posted by Paul Elliott

Sorry, the answer is no:

Baud rate refers to the number of symbols per second. The raw bit rate depends on the baud rate and the number of bits encoded by each symbol. QPSK (Quadrature Phase Shift Keying) is an example of a modulation method that encodes two bits per symbol. In QPSK the bit rate is double the baud rate.

There are many modulation schemes that use variations in phase, amplitude, and frequency to carry many bits per symbol. Look at the Shannon theorem to see how many bits can be pushed through a noisy band-limited channel, but bitrate and baudrate are definitely different things.

In spite of this terminology disagreement, there is no question that XGate and other optimized protocols / applications can deliver a dramatically improved bitrate. As I've said before, I've done the tests myself and as a result am a satisfied XGate customer.

Exactly. And all that does not increase the native satellite data rate. But I've given up halfway between application-application bitrates and free email. Anyway, soon Pactor4 with double the speed and free unlimited airtime

p.s. Using PPP framing to encapsulate IP and then exchange email over that is totally weird. The overhead caused by that is outrageous. I don't know much about Xgate but did use UUplus for years and they use the good old UUCP protocol instead which makes 100% sense. Couple that to a strong compression algorithm and you will have an optimized system that is very hard to beat.

ciao!
Nick.

[unbusted67]

I don't know what it is but it seems like every thread I start dissolves in a nerd fest.

This is the story of my life, why can't my threads dissolve into hot girl fest instead?

[GeoPowers]

Because you asked about SSB vs HAM vs SAT phone and not Nair vs vs Hot Wax vs Razor.

[unbusted67]

your logic is flawless

[goboatingnow]

Originally Posted by unbusted67

You know I think the thing we aren't really talking about, and a determining factor, is a sat phone's uselessness when it comes to contacting other boats around you. Sure you can call 911 but can you talk to the ship that is 50 miles away or the other cruisers in the area to check for firsthand weather updates?

In an emergency now under GMDSS rules you don't contact ships around you , you contact a rescue centre and then they put out calls for ais to the appropriate vessels . Sat phones work very well for that.

[osirissail]

I think he was referring to other cruising boats and not necessarily container ships, freighters, and other mega-tonnage vessels. And you have EPIRB's for major disasters.

Until the vast majority of cruisers - say in the Pacific Puddle Jump or the Atlantic Arc's are sat phone equipped SSB - IMHO- is a vital inter-cruising boat communications method. And I don't think sat phones can do "party/group calls?" They are strictly one to one.

[s/v Jedi]

They should assign satellite phone numbers that are the same as the boat/ship MMSI number, regardless of which satellite system is used.

But thatwould be too logical I'm afraid...

cheers,
Nick.

[goboatingnow]

Originally Posted by osirissail

I think he was referring to other cruising boats and not necessarily container ships, freighters, and other mega-tonnage vessels. And you have EPIRB's for major disasters.

Until the vast majority of cruisers - say in the Pacific Puddle Jump or the Atlantic Arc's are sat phone equipped SSB - IMHO- is a vital inter-cruising boat communications method. And I don't think sat phones can do "party/group calls?" They are strictly one to one.

For the last few years sat phones are the majority comms method on ARC boats

[osirissail]

Originally Posted by goboatingnow

For the last few years sat phones are the majority comms method on ARC boats

Considering the cost of entering the ARC, I suspect a sat phone is not considered an unreasonable extra expense.

But, from the rules and regulations of the ARC
"Long Range Communications Equipment An SSB radio (with pactor modem) or satellite communications system capable of sending and receiving email messages whilst at sea. This paragraph does not apply to Rally Portugal."

So SSB is still the traditional piece of communications equipment for ocean crossing cruisers with sat phones gaining rapidly.

Still that doesn't answer the problem of operating "nets" where everybody can hear what is being transmitted from a particular boat. Especially if the boat is in a urgent situation and needs to talk to somebody, anybody in the "fleet."

[Paul Elliott]

Most of the ocean races I've looked at (Pacific Cup, Transpac, Singlehanded Transpac, others), and the ISAF Offshore Sailing Rules (the controlling rules for most ocean races) now permit satphones as a substitute for SSB. This has been an evolutionary process, but this policy has been generally adopted over the past five years. Most races still require at least an SSB receiver as an emergency backup. These rule changes reflect the fact that for safety and weather communications satphones are a reasonable solution for many people. This policy also factors in the fact that more and more boats will be using satphones, and on race boats the extra weight and space required for a good SSB installation is not a trivial factor.

That said, SSB remains an excellent solution for high-seas communications, and will continue to be preferred by many. I have both, and wouldn't want to give up either.

[medicrene]

Just to put my two cents in about reception of Weather Fax, the most common problem related to getting a poor signal is not the modem (pactor or sat), the problem is the reception. Consequently, the solution is the antenna and proper tuniing of the signal. Keep in mind that NOAA publishes the frequencies for these broadcasts, however unless you read the fine print, you will not notice that the transmission frequency is actually 2 KHZ (or MHZ...i have to look at it again) below the published frequency (I do not know why). Play with the system and get used to recieving these transmissions much earlier than when you really need a good weather forcast. If the weather at home is foul, call up the weatherfax to see what foul weather looks like on the screen.

Good Luck,

The Witchdoctor

[SPARK]

Also remember that the solar radiation seems to affect SSB more badly than sat phone. Solar radiation has a cycle. We have just past the worst of the cycle so reception should be improving.
For all those people that have been complaining about reception for the last 2 years, maybe you should try to check your reception now. Remember that in the next few years the radiation will be even less according to the cycle and reception will be continuously improving.(for SSB)

[cnx123]

HI There given the cost of a new SSB installation,what about Fleetbroadband such as Addvalue Skipper 150,seems equipment cost similar to SSB and gives you the advantages of satphone plus email etc.Still new at this but am considering either the traditional ssb/pactor or the fleetbroadband 150.The cost of airtime is a factor and as mentioned before you do not have the group chat/party line as on SSB.
Any thoughts???
Chers Nig