Brian Rankin wrote: > > Everybody, > > Thanks for your suggestions! I am located in San Francisco, and would be > glad to volunteer as coordinator. I hope to travel to Ghana in August > 2000 to provide further mentoring for the computer lab, so anything built > I can take with me as personal checked luggage. That way everything goes > with me thru the airport, and my host can help me deal with any baggage > issues. I don't believe that cameras/pictures are allowed in the Accra > airport, the military is very strict about enforcing Ghana's airport > security laws. > > I can form a separate email list for this project, so that discussions > don't conflict too much with the wearables list. Or, we can keep > communicating via this list. Let me know what you think. > > There are actually two issues which could be tackled: > > a) small computers based on the embedded-computer/wearable technologies. > There are two advantages: 1) easy transportation to Ghana, and 2) low > power requirements. Ghana constantly has brownouts and blackouts, with > massive power surges. Every time the power goes out every device has to > be unplugged, else it will burn when the power surges on. I saw a power > regulator get fried black, as well as a television. If these computers > used low enough voltage, perhaps they could be supplied with solar > energy....maybe? Or a solar-charged car battery? Also, power is often out > for 4-8 hours at a time; it really interrupts the flow of learning in the > lab. The thing that has to be happening here is huge inductive surges on power-up. BAD news for computer hardware! I've seen XT/286/386/486 class machines run off a 12V golf cart battery with some voltage regulation and DC-DC voltage converters, for robotics and/or car MP3 usage (You might look around for the MP3 players, to give that a thought. If you cannot find some, ask & I'll pass you URLs, I'm good with search engines.) Can you get Golf Cart batteries, or other deep cycle lead-acid batteries, in Ghana for reasonable prices? (Marine Trolling motors are the same thing, only lots more pricey than Golf Cart batteries, you would want deep-cycle batteries, definitely, here.) Or could get them here & ship there. If you built a battery charger that was self-protected enough to survive the blackouts (Can be done; it might be easier to just set up a latching relay and let power dropouts open the relay, once power's been on for a while you turn the relay back on!) you can also AC charge the batteries at night potentially, a Good Thing as the sun's not up at night <G> It's really hard on car batteries to deep cycle them (You could just use them as a "surge buffer", and keep them full most of the time from solar power - you can use mirrors to increase solar radiation onto a solar cell to give it more output, "Don't melt the solar cell" though, you might have to cool it if you use large mirrors!) Also could use something like a stirling or other steam engine, solar driven or ??? > b) A fat pipe to the Internet. The ISPs in Ghana are crap. They way > oversell their service (and only the elite of Ghana can afford it), and > it is extremnely slow and unreliable. The school is currently sharing its > one phone line with the modem on the Linux server, which means slow 'net > access for a couple of hours a day. I'd really like to find a way of > bypassing the ISPs and the telcos. DSL and cable is not an option in > Ghana. DirecPc/Hughes do not cover central Africa. Nevertheless, I > would think that there _must_ be an alternative to land lines. Is there an amateur radio service in Ghana? Could do some kind of amateur satellite, we're talking lots of money here though, I think? > Maybe we could begin by working on the specs for the computers to be > built. I saw an earlier post indicating that using a Linux interface might > be an alternative to Win95. I think that Linux would be fine, as long as > we can make it easy for the children to use (Staroffice instead of MS > Office, computer games, etc). That could be a good answer. Need a list of components, and to know what way you want to proceed, what the needed resources for each computer are, etc.? What sort of way makes the most sense - you know what is needed better than we do! > Lastly, whatever we build/supply has to be sustainable by the folks in > Ghana. In the past, several well-meaning people have made fine > contributions to schools in Ghana, but neglected to ensure that the > Ghanans had the training/equipment to deal with problems, so the > contributions weren't of lasting value. Spare components and "clusters" of identical machines are good, here; What else is needed? Tie a Linux guru to each machine or something? <G> (I've been joking about "kidnapping" one local guy to help me with a Linux problem, inside joke I guess. I'll get him to go willingly <G>) I'd guess voltmeters are available at that school, crimp tools for Coax for Ethernet (or for 10BaseT?), spare hubs might be good, etc.? What training's needed? How to provide that over time, I wonder? A good question for me to ask, too: What's Ghanan power set for? 110VAC, 220VAC? 50Hz, 60 Hz? <G> Would it help if they can e-mail someone in the US who can answer questions, and/or hunt down spares and ship them there, as needed, perhaps? I'm not super rich now, but can try to help somewhat. Even though the ISPs there are not "optimal", an e-mail link for asking for help should improve things here, too! > Please let me know how you want to proceed. Again, many thanks! > > Sincerely, > > Brian Rankin Mark -- I re-ship for small US & overseas businesses, world-wide. 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