Como cargar bootloader de un Arduino a otro, Beeduino : Homemade Arduino Uno for $6

http://www.instructables.com/id/Beeduino-Homemade-Arduino-on-a-Budget/step7/Bootloader-Burning-using-another-Arduino/

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Step 7: Bootloader Burning using another Arduino

Boot loader on a micro controller is basically its operating system. It tells it how to communicate and respond. The arduino boot loader allows it to be programmed via USBASP. First download the latest Arduino IDE here and install it.
For burning the boot loader you need an Arduino Uno. Follow the following instructions carefully

1. Connect the Uno and select the port. Open the example ArduinoISP and program it to the Uno.
2. Connect the Uno to Beeduino as shown in the second image.
3. In the Arduino IDE, In Tool > Programmer, select Arduino as ISP
4. Then in Tools click on Burn Boot loader. If all is well the boot loader should burn in a few seconds.

If there is a problem do the following checks.

1. Double check all the connections. They should be firm.
2. Remove and redo the connections.
3. Recheck the board to see if you made any soldering mistake.
4. Remove the USB cable from PC and reconnect, then try again.

I hope you are able to burn the boot loader successfully.