#10246 - 10/27/02 03:28 AM
Re: New Wallet Emergency Card
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Old Hand
Registered: 08/22/01
Posts: 924
Loc: St. John's, Newfoundland
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I know I'm a math geek, so this may not be something everyone wants to have, but I'm going to put a table of trigonometric values (probably either sines or tangents) in my PSK.<br><br>Why? Because I also plan to put in a steel tape measure, 1 metre long. (I just bought one for a $ in the "Everything for a Dollar" store in the mall. Undid the screw in the back, pried the case apart - presto, a 1 metre long steel tape measure that I think I can fit round the inside of my Altoids tin PSK. With this and a set of trig tables, I should be able to calculate my latitude a lot more accurately than with any protractor I could fit inside. <br><br>To measure your latitude - put a vertical stick in a horizontal piece of ground. At precisely high noon - when the shadow is at its shortest - measure the length of the shadow. Divide it by the height of the stick; this will give you the tangent of your latitude. <br><br>For example: Suppose your stick is measured at exactly 48 cm high. At noon, it casts a shadow 39 cm long. This gives a tangent of 0.8125, which according to my Windows calculater equates to an angle of approximately 39.1degrees. You would be approximately 39 degrees 6 minutes N. (Of course, someone would have to calibrate for the time of year; the above example would only be correct at the equinox, I believe.)
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"The mind is not a vessel to be filled but a fire to be kindled." -Plutarch
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#10247 - 10/27/02 07:11 PM
Re: New Wallet Emergency Card
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new member
Registered: 10/21/02
Posts: 45
Loc: United Kingdom
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Why not go the whole hog, and get a small sextant? (OK, it won't fit in the wallet.)<br><br>My girlfriend got me a small one last Christmas, and I've had great fun mucking around with it. Not entirely sure I want to replace the GPS yet, but the US gov can switch off the GPS; the Sun and stars are a little harder to get at (barring smoke grenades :-) ).<br><br>And as a bonus for a math geek, you get to play with lots of sinhs and coshs too! What more could you want?
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#10248 - 10/28/02 04:52 PM
latitude
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Anonymous
Unregistered
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Thats neat. Have you got a reference for that? Say...a book I could order at the book store.
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#10249 - 10/29/02 12:25 AM
Re: New Wallet Emergency Card
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journeyman
Registered: 12/12/01
Posts: 73
Loc: Western / Central Australia
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This may be a dumb question - but how will knowing your approximate lattitude help you navigate to safety if you don't have a map? <br><br>And if you have the map, why would you need to know your latitude?<br><br>Otherwise a great exercise to show young'uns how it all started (the global map business that is) and handy in a liferaft or a desert isle !
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#10250 - 10/29/02 01:23 AM
Re: New Wallet Emergency Card
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Old Hand
Registered: 03/13/02
Posts: 905
Loc: Seattle, Washington
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miniMe,<br><br>Nice job. I have also been working on a smaller list of important things for my wife (my list is too complex and huge). We have recently started to formalize our expected responses to various situations. Having emergency numbers, contact numbers and a quick list of what we expect each other to do in an emergency has been my focus. I was not sure how I was going to provide her tips on the use of her office or home kits. This is a great format to build on.<br><br>Thanks
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#10251 - 10/29/02 01:36 AM
Re: New Wallet Emergency Card
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Old Hand
Registered: 08/22/01
Posts: 924
Loc: St. John's, Newfoundland
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First of all, what do you mean by "a map"? A nautical chart? A WAC, or aeronautical sectional? A 1:50,000 topo? A street map?<br><br>Second, who said anything about navigating to safety? I was thinking of sending out an SOS on my FT-817 (a 5-watt portable capable of sending and receiving morse code on short wave). Yeah, I suppose the SAR guys could home in on my transmission - if my AA alkalines didn't die in the meantime - but how much better it would be if I could give an approximate lat/long for them to start searching?<br><br>Finding the approximate longitude isn't hard, as long as you have a reasonably accurate wristwatch. I have Zulu time (aka UTC or GMT) programmed into mine, but as long as you know what time zone your watch is set to, you can figure that out. Note the time (UTC) when the shadow is shortest (that's what I call 'local solar noon' - I'm sure there's a technical term for it). Subtract 12 hours; if the answer is negative, add 24. Express the number of minutes as a fraction; e.g. if it's 1634 hours (that's 4:34 p.m.) then your number is 4-34/60, or about 4.56. Divide by 24 and multiply by 360 (or if you're lazy, just multiply by 15) to get 68.4 - approximately 68 degrees 24 minutes West. (I'm purposely doing the math in my head, so I may have screwed up; if it was a l&d sitch, or if my numbers were clearly out to lunch, I'd sacrifice some of my Rite-in-the-Rain paper to doublecheck it :-)<br><br>If you're out hiking - or even driving - and get lost, you probably don't need this. If you've got a GPS, make sure you record your position *before* the batteries die. <br><br>But if you're like one of those unfortunate Chilean soccer players, and you've been rudely awoken out of a nice comfortable sleep to find yourself surrounded by dead team-mates and a whole bunch of snow blowing through a gaping hole in the fuselage, it might be nice to be able to estimate your position, even if only to locate yourself quickly on the pilot's map.
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"The mind is not a vessel to be filled but a fire to be kindled." -Plutarch
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#10252 - 10/29/02 02:15 AM
Re: New Wallet Emergency Card
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Old Hand
Registered: 03/13/02
Posts: 905
Loc: Seattle, Washington
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aardwolfe,<br><br>OK I am sort of getting this. <br><br>tan Angle = length/height at local noon, so <br><br>ATan ( length/height) = angle of sun or approximate latitude.<br><br>Presumably, you can determine longitude with more accuracy (time at local noon) then radio SAR and ask them to fly the longitude and apply necessary corrections for time of year variance for latitude.<br><br>If anyone is interested SAR of British Columbia has Pocket Cards (page 4) that shows how to determine the height of an object given the angle from a clinometer equipped.orgpass. Presumably you can shoot the sun with your compass at local noon and get your approximate latitude. Measuring the stick is easier as you can mark and find local noon more precisely without burning out your eyeballs.
Edited by Schwert (10/29/02 02:15 AM)
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#10253 - 10/29/02 02:27 AM
Re: New Wallet Emergency Card
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Anonymous
Unregistered
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My thought was to get the basics of the response down in broad strokes in something that could fit in the wallet (along side a fresnel lens ). I expect that each of the eventualities will be supplemented by further information stored elsewhere. This is what should immediately come to hand if and when something goes severly bad for whatever reason. <br><br>Our vehicle kits all contain the Haynes manual and I will add a basic survival write-up on what to do if stranded in (cold, hot, downed electric wire, remote ... pick your scenario) in the car. I expect that the Haynes manual will be useless for my wife but it did get me moving once and probably will again. Without it the array of tools and duct-tape and coat-hanger wire is less usefull. I welcome any input for these survival tips for the stranded motorist scenarios (books, software, specific instructions...)<br><br>Our BOB's should have larger maps and more descriptive information on Fire, Water, Food, and Weapons when they are done. These haven't been completed yet so I welcome any good suggestions on what to include (from books to software to notes).<br><br>The individual Belly Bags we each have are fairly self explanatory - Poncho for staying dry and space blanket for staying warm, bandaids for cuts, knifes to inflict cuts, etc...<br><br>I am using Willy's PSK cheat sheet for the PSK's. Only seems natural.
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#10254 - 10/29/02 03:03 AM
Re: New Wallet Emergency Card
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Old Hand
Registered: 03/13/02
Posts: 905
Loc: Seattle, Washington
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I am also carrying Willy's Cheat Sheet, good product, good price!<br><br>I have been trying to distill my lists down to more managable chunks that would be useful and available. I have broken it down to emergency contacts, State and Local community numbers, Expectations, HAM radio section, ACS RACES frequency lists, Radio nets, Bus schedules, and then my big list of junk that I somehow have intrepreted as useful information.<br><br>I have decided that my wife needs only have the Expectations decision tree, Emergency contacts, State and Local numbers, and the basics of using her kit. I am going to adapt your wallet format for her and a slighty expanded one for me.
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