Saturday, June 12, 2010

How I learned to love SPS mail, and live with the QRM

Definitions:
SPS = Satellite Phone Store
QRM = Radio Interference from Man-made Sources (as opposed to QRN = Natural Sources; e.g., lightning)

When Bill and I first started making plans to rent an Iridium satellite phone, way back in March, it was with the idea that it would give us a way to make phone calls from the boat in an emergency. At $1.25 a minute, we certainly wouldn't use it for everyday chit-chat and email. But something happened during the shopping process. I found lots of places that would rent us a phone for $60 a week, with $1.95 a minute airtime. For a ten-week rental, that would be $600 just for the phone, then you would need to rent the external antenna and the data kit for connecting the phone to the computer (as a modem), and then buy a SIM card for $975 (500 minutes x $1.95 per minute). Plus tax ($$$), two-way-shipping ($$$), and insurance ($$$). Then I discovered the Satellite Phone Store in Florida that was selling used phones outright for $695 and offering a 500-minute SIM card for $625 ($1.25 per minute). So I emailed them and we made a deal, phone, 500 minutes, and all accessories included, for $1700. The phone arrived, with all accessories, a week later. But it was DOA. So I called them up and, after playing phone tag for about a day, they agreed that the phone was defective and they would repair it if I sent it back, which I did. In due time, the repaired phone arrived and it did work, for voice. I did not test its data capabilities until I got to Hawaii.

Long story short (I know, too late!), when I got to Hawaii, I hooked the phone up to Bill's computer and, lo-and-behold, the data capability did not work. Since departure date was about a week away, too short to get a new phone, I was freaking out. I spent hours researching this problem on the Internet and leaving panicked messages at SPS. I even went over to Rick's house to try it on his computer, and Bill and I went to Radio Shack to buy replacement data kit parts, but nothing worked. Finally, primarily through guesswork, I changed a modem setting and got it to work, but not at the full specified speed of 19,200 bits-per-second. Does anyone remember an era when dialup modems were rated at less than 56 kbps? Anyway, it was working well enough at 9600 bps that we could shov e off and be reasonably confident that our SPS email (spsmail.net) would work for us.

However, this left me hugely anxious, but not for the obvious reason. The obvious reason would be that I had bought what I thought was a 19,200 bps modem and all I got was 9600; in effect, I was baited and switched. True, but no big deal. What really concerned me was the possibility that this symptom indicated a more serious hidden problem and that the whole thing might fail at any moment. That was eating at me.

Once we were at sea, I had two three-hour watches every day when I was mostly alone, inventing mental tricks to stay awake, and stewing about this modem situation. Finally, one day after my watch, I sat down and wrote a long scathing email to SPS about how unhappy I was. That led to a series of tech support email exchanges that eventually involved the company UU+, the Morro Bay software vendor for SPSmail. I had determined that I could force the modem into the 19,200 bps mode, and it would work, but just until I ran SPSmail, which would then cause it to fail. At this point, one of the UU+ tech support guys recognized this lower data rate as a characteristic of an older generation of satellite phones, one that cannot be upgraded in the field. But at least it reassured me that this was a known problem and this was normal operation and the whole thing was probably not going to fail at any moment. So I was able to accept that this phone is working perfectly, albeit at 9600 bps, in total accordance with its (dated) specification. Whew!

During this whole interaction with SPS and UU+, I developed a new theory about how SPSmail relates to Sailmail. As I said previously, I had no expectation that I would be using SPSmail all day every day, but that's what happened, and here's why.

The satellite phone can be left on 24/7; it has its own internal battery and its cigarette lighter charger draws almost no power. While it is on, it can receive text messages, which are free and which cause the phone to ring. The HF radio draws more power from the main ship's battery so we leave it off most of the time.

The satellite phone can be used any time without any planning or preparation. It is always ready to go and it is immune to ship-board QRM. The HF radio doesn't work very well when the ship's battery is low, and it doesn't work at all when the engine is running, due to QRM from the alternator. Plus, even when the battery is up, and the engine is off, the HF radio is plagued by QRM from the autopilot, so the on-watch crew (usually Kathy) has to hand steer while I use the radio. Note that this will not be an issue during the race, where autopilots are not used.

The satellite phone is a dedicated service, just like a land line, not shared. Each Sailmail shore station is shared among all users in range, like a giant party line (you've heard of those?). While Sailmail has lots of shore stations, only one or two are reachable at any one time from any one location. So all vessels in your area will be using the same few shore stations. This has not been an issue during the delivery because there's nobody else out here. It's very rare that I hear another station sending email. But I can remember in previous races, with 25 boats sailing more or less in formation to Hawaii, when we would have to wait an hour or more, listening to the radio, before we would be able to use that frequency. And sometimes I just waited until three o'clock in the morning to improve our chances of getting in.

Finally, satellite phone email is much faster than Sailmail and its file size limitations are higher. If you are willing to pay for the airtime, you can send very large files like digital photos and videos.

But what about cost? Sailmail is $250 a year, for up to 90 minutes a week usage. If you can use it year-round, as a world cruiser might, and you have no urgent email requirements, it's a smoking deal. But if you jam all your offshore email activity into two three-week trips, like we do, that's $125 a trip. SPSmail is $15 a month, or $15 a trip, plus airtime, say $75 a trip.

Conclusion: Cirrus is already equipped for Sailmail, to the tune of several thousand dollars in HF radio and PACTOR modem equipment, plus an extensive antenna system that works extremely well. So I am very happy that we have paid the annual Sailmail membership fee and I will happily use Sailmail whenever I can, like for collecting comments from all our blog readers. I especially like that it's a little more technical, including the Morse code signoff. But for the emails that have big files attached, like our blog entries, and for emails that just that have to go out now, like tech support exchanges, or dock party arrangements, even when the ship's battery is half dead, or, like today, when the motor will be running for 24 hours because we have no wind, I'm very happy to have SPSmail too.

This is my current opinion, based on what I think I know. I am always open to other opinions, and to being further educated. Comments? ~~Chris

4 comments:

  1. good troubleshooting story. i remember 1200 baud. ugh. and i remember being thrilled with 9600 too. but back then few dreamt of sending video or big photo files. i'm just impressed and glad to hear you're so tech savvy that you can suss all the modern comm stuff out. it's all way over my head.
    thx - sam

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  2. PCYC has posted the division assignments. We start on Tuesday July 6,1215PDT in div B as slowest boat with PCR=605 (we had 600 in PCup08, 607 in PCup06, 611 in PCup04). Fastest is 563. We are now the 19th slowest out of 56 boats. Pegasus is fastest with 361, the one you had beaten on one day in the transpac :-))).

    (I wonder if the table will survive posting)
    Division B Tue 6 July 12:15
    Cirrus Bill Myers 40 feet 605
    Tiki J Scott Dickinson 42 feet 602
    Coyote Connie & Steve Hill 42.6 feet 596
    Bequia Dennis B. Ronk 40.6 feet 590
    Relentless Paxton/ Zippel 32feet 590
    Sweet Okole Dean Treadway 36 feet 584
    Tiki Blue Gary Troxel 41.8 feet 581
    Scaramouche V Peter Heiberg 49 feet 581
    Pneuma John A. Mendoza 47.3 feet 563

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  3. so I wasn't hallucinating in PCup08, these things can do a whopping 19k!

    Aloha, from a dismal 6000k land line DSL,
    Ulli

    p.s. forgot to sign the previous comment, but there may be a mild chance that you have guessed it already.

    ReplyDelete
  4. Breaking News courtesy of NY Times

    "U.S. Discovers Nearly $1 Trillion in Afghan Mineral Deposits

    The United States has discovered nearly $1 trillion in untapped mineral deposits in Afghanistan, far beyond any previously known reserves and enough to fundamentally alter
    the Afghan economy and perhaps the Afghan war itself,according to senior American government officials.

    The previously unknown deposits -- including huge veins of iron, copper, cobalt, gold and critical industrial metals like lithium -- are so big and include so many minerals that
    are essential to modern industry that Afghanistan could eventually be transformed into one of the most important mining centers in the world, the United States officials
    believe.

    ReplyDelete