“I was inspired a while back by the simplicity of the FFT application written by Shane Ormond and featured on the 43oh blog. It was easy to duplicate and I’ve made a few changes, additions, and such that seemed worth documenting. I didn’t have a signal generator other than the 1kHz square wave on my oscilloscope and some clunky code that I wrote for a microcontroller so I ordered an inexpensive AD9850 and hooked it up to a FR6989 LP so I could use the LCD to display frequency. I’ve been pleased with the AD9850 and it is hard to beat it for the price. The sine wave is more than sufficient for my needs up to 40 MHz – I don’t see any deviation from the scope.”