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A useful and fun project from Gary /  AA7VM
This project can be found in QST NOV 2005
Contact the author AA7VM for the HEX  Code

I did not fabricate my own board for this project, as the pitch of the AD9833 was too fine for my Homebrew laserprinter / acetate / heat etching process.
I instead purchased the board from FAR CIRCUITS

The project uses an AD9833 programmable DDS chip
which is connected to the parallel port of a PC.
Software for the DDS is available from Analog Devices
and can provide sine, square, ramp, and sawtooth waveforms
up to around 1 MHz or more.

My mods of the original project include a variable output port, output DC blocking capacitors, and a power LED.

Here is a photo of the PC running the DDS at 10 KHz:
working dds

Front / rear / and inside the project:
DDS front

DDS Rear

inside dds