Using the RTL-SDR as a transmitter
OK, this is very low power but it shows you what can be done. A QRPP transmitter or signal generator anywhere between 500MHz and 1.5GHz.
Please note the image below is not on my blog (it is linked as shown) and will be immediately removed if this is a problem.
Marvelous how this is done nowadays. I remember BIG tubes and now these mico units are simply amazing!
Inside an rtl sdr defanation