LED SOS without programing?

If/When i get my pilots license, I would like to build a survival kit that contains a high powered LED "flare" that flashes ..._ _ _... I don't wanna over complicate things by having to program a microcontroller. Maybe a 555 timer?

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Johenix7 years ago
Let me see, SOS from a digital source at minimum requires a count of 24 bits, 2^5 in binary is the natural next largest binary number, so we would need a NE555 (CMOS version prefered) and 5 flip flops (CMOS prefered) and a ROM (read only memory) or a logic network to convert the binary count to morse.

Logic summary:
#         output       Binary count
0-7     off              00000-00111
8         on (dot)    01000
9         off              01001
10       on (dot)    01010
11       off              01011
12       on (dot)    01100
13       off              01101
14-16 on (dash)01110-10000
17       off             10001
18-20 on (dash)10010-10100
21       off             10101
22-24 on (dash)10110-11000
25       off             11001
26       on (dot)   11010
27       off             11011
28       on (dot)   11100
29       off             11101
30       on (dot)    11110
31       off              11111
32 (0) off              00000

This should give you the basis for an SOS generator. 

This sounds like a solution. Is there anywhere with an example of such a circuit or a list of parts with part number examples?

I am looking to just send a IR/RF pulse of bits based on a button press. Like a TV remote but single button and pre programmed code on a rom which could be 8-32bits. I haven't had much luck finding such a circuit in my apart from this thread!
sockless7 years ago
Maybe a a few transistors, a decade counter and a 555 would work, you could potentially just use a capacitor for an oscillator instead. To be honest, using a picaxe would be the easiest solution, it'd take only a few lines of simple code to do.
santy227 years ago
 Get the java app for your phone, or just buy a beacon. Serioulsy MORSE CODE?
Johenix7 years ago
Better answer: Get a ham radio Iambic keyer. There are some that use one IC, a lithium coin cell, no on/off switch and have a sleep current of about a pico amp 1/1,000,000,000,000 AMP. You use the keyer memory (60 characters) to hold the SOS and maybe your tail number. 
Program it in becon loop mode and then set the trip switch. It loops continiously.
Johenix Johenix7 years ago
That's the "PicoKeyer" or "PicoKeyer Plus" by Dale Bodkin (N0XAS) or see www.HamGagets.com
rickharris8 years ago
6 mico switches set in a circle with a rotating cam to set the switches. buy an emergency torch that does this they are around even my mobile phone will do this.
You don't even need a 555 you can use a couple of transistors in a multivibrator circuit. You need an "Astable" multivibrator like this link shows.
http://www.absoluteastronomy.com/topics/Multivibrator

Size at least one transistor to suit your diode current, and replace R1 with your LED.
Make a little 'Wheel' with one contact point, and set up multiple circuits. when the wheel touches a contact point, that circuit lights up. the wheel is run by a motor.