عرض مشاركة واحدة
قديم 08-03-2011, 08:27 PM رقم المشاركة : 2
معلومات العضو
م .نبيل زبن
المؤسس
 
الصورة الرمزية م .نبيل زبن
إحصائية العضو







 

م .نبيل زبن غير متواجد حالياً

 


افتراضي


Pin 5 of the serial port connector (the black wire in the photo) connects to the ground pin of the oscillator. Pin 4 of the serial port connector goes to the power pin of the oscillator. The drawing shows the transmitter from the top (pins pointing down). The photo below shows the oscillator upside down* with the pins facing up



The green alligator clip attaches to the antenna* which can be any long wire. It is attached to the output pin of the oscillator. The remaining pin of the oscillator (the one nearest the sharp corner) is not used.
Your Computer Controlled Transmitter is now complete!

Controlling the transmitter

To send a message* we now need a computer program that can convert what we type into Morse code* and turn the oscillator on and off in the short and long pulses (dots and dashes) that are required.
A program to do that (for the Windows operating system) can be downloaded by clicking here. Save the ZIP file on your computer* use a ZIP file decompressor to unpack it* and then double-click on the resulting MorseCode.exe to start running it.




[IMG]Once the program is running* you will see a window like the one above. Type something in the window (such as "Hello there!") and then select the Transmit item in the Radio menu. Your transmitter is now sending your message.[/IMG]



can select how fast the message is sent by using the Speed menu.
You can control which serial port to use through the Com Port menu




The Radio menu has three selections we have not discussed yet. The AM Low Tone selection sets the tone you hear in the AM radio to 500 hertz. The AM High Tone selection sets the tone to 1*000 hertz. The CW selection is only for short-wave radios that have an SSB or CW mode. This selection does not modulate the radio signal* so an AM radio will just hear clicks. This selection allows the signal to be heard farther away* but requires a more expensive short-wave receiver. I have used the



Grundig YB 400PE radio with great success. It usually sells for about $150.00



you are a computer programmer* and would like to look at the source code for this program* you can download it here. There is also a much simpler* command-line version of the program here.


Receiving the code with a computer


Until you have learned to decipher Morse code in your head* you will want to have a computer do it for you.
There are many free programs floating around the Web that will do this for you. One such program can be downloaded here. I won't go into its operation (since I didn't write it)* but it has a Help menu* and it is fairly straightforward to use. You will need an audio cable to connect the radio's earphone jack to the computer's sound card input jack* but that is all the hardware required.



You can see it working in the screen shot above* decoding our endless loop of "hello there".







رد مع اقتباس