Iridium GO or SCS P4 Dragon tnc

[Emerald Sea]

We have and use both the P4 (Airmail/Sailmail) and GO (with PredictWind) for international bluewater sailing. They complement eachother.

If you can be more specific as your cruising plans, needs, then I can provide a more focused reply.

[Auspicious]

Originally Posted by Paul L

Huh, I have a ton of experience with the Pactor P4. It's still hard to comment on your comparison request without knowing what you want to accomplish.I

I agree with Paul. It helps to understand your cruising plans and existing comms infrastructure. Nevertheless, I'll give it a shot.

The P4 like its predecessors has an outstanding weather fax demodulator. What you can get from weather fax is head and shoulders above what you can get from gribs. Of course you can get weather fax without a modem using a computer sound card. You can also get gribs over Pactor (P2, P3, P4) free from Saildocs over Winlink (free) or Sailmail (cheap) as well as access pay-for services like PredictWind.

For email, P4 is much faster than Iridium - about 4x faster.

Phone calls over HF/SSB are much more logistically awkward than the GO! or any other satellite-based system. Ham phone patches or commercial ship-to-shore like Shipcom or Brunei Radio take some getting used to.

As others have noted the Iridium apps leave something to be desired. XGate is much better but you pay extra for that. If you are willing to live with gribs (yuck) PredictWind is a better experience than the alternatives; the data is the same its just so much easier to get it on board.

Assuming you have an existing HF/SSB that performs well adding P4 is an easy choice. If you have ongoing time-sensitive business ashore or elderly parents in health care that you manage on a day-to-day basis you cannot beat satellite. If you go the satellite route I'd still set up for weather fax to get synoptic charts.

Originally Posted by Paul L

It is not legal to use on Ham bands, it is legal on the SSB frequencies used by Sailmail.

Paul is exactly correct. You CAN use P4 on ham bands outside US waters even with a US license. You CAN use P4 on marine bands anywhere.

The difference between P1 on the KAM and P4 (or even P3) is huge. Not only is it faster but many Winlink RMS no longer support P1 so you'll find you have more options for connections.

[AA3JY]

Originally Posted by AA3JY

It's Amateur Radio legal anyplace else other than CONUS..Read the Pactor forum

FYI.. the P4 restriction was lifted temporarily during the Puerto Rico hurricane relief efforts to move communications from the stricken area to the US

http://www.pactor.com