Where can I get a circuit design to make a circuit to light two mini- incandescent bulbs on my radio-controlled air craft carrier's topmast signal lights to send the message,"Where is the sixth fleet". Power source is two "D" cells.Size and should be minimum.
It can be done with a PIC micro controller and a a power MOSFET. Part cost maybe less then 10 $ However you would have to program the PIC ,and that required some experience and a programmer.
If you designed your own with a microcontroller, the "minimum size" would be quite small. If you need someone else to design it for you, I'd suggest looking at what HAMs call a "memory keyer". You should be able to find a kit or fully assembled model that would spare you all the microcontroller programming. You'd then follow the directions to program your message into the keyer using an actual key and hard wire the keyer to play it back continuously (some kind of beacon mode).
Use a pic10F200 six pin micro. with just 2 LED's on the GPIO port you could make a table with a bunch of RETLW 's and a delay between each loop. It would be quite easy really.
If know where I can get the signalman light codes for each letter, I'll post the pic assembler code here for you free of charge...
'To confuse enemy cryptanalysts, radio messages contained nonsensical phrases or ?padding.? But when New Jersey?s radio watch decoded the message, it retained the end padding: ?Where repeat where is Task Force
34? The world wonders.?
Unfortunately, the second sentence appeared logical in context, and when Halsey read it, he went into shock. Chester Nimitz, a gentleman to his core, had seemingly jabbed Bill Halsey with a bitterly sarcastic rebuke.'
In addition to the other ideas already mentioned: You could use the output from a Radio Shack recording module (# 276-1323) to drive a mosfet or bipolar to flash the lights. You'd need to record the morse at about 15 wpm for the message to fit - the module stores
20 seconds of sound. The playback would be at the same speed. You would need to provide 9 volts for this.
A memory keyer gives you more message room and control over the playback speed, but costs more. A micro gives you ultimate control, and is cheaper - but you have to know how to program and use it.
With all three ideas, you need to use a mosfet or bipolar to flash the lights. The lights take more current than the module, keyer, or micro can supply directly. And you need to provide the proper voltage to whichever device you use.
I came across "Secret Messages: Concealment Codes And Other Types Of Ingenious Communication"
in a used book store. It is full of such "coding." No way is the book worth $30. Geez, I thought it was a stretch at $2. However, I now know the prison gang coding schemes without having to risk my butt (heh heh) in prison.
Well, It's snowing here in New England and I got the day off :)
So... Now I have some time to kill...
Here is the pic code...for the pic10F200...ENJOY!
;14-Jan-2008 snipped-for-privacy@punkass.com ;for 'sci.electronics.design' ;------------------- list p=3D10f200 ; list directive to define processor #include ; processor specific variable definitions
#define dot 0x01 ;. lsb led on, msb led off #define dash 0x03 ;- both leds on
main movlw B'01000000' ;bit7=3D0 enables sleep mode option ; movlw B'00001000' ;port line direction 1=3Din 0=3Dout tris GPIO ;copy w tristate, gpio outputs ;
If you're using incandescents, you might want to put a medium- value resistor across the switch, to keep the filament warm, but not lit up; this will increase bulb life dramatically and maybe help with the switching edges.
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