Last weekend, a number of club members got together and built a Digital Oscilloscope Kit. The cost was only $28.00, and the scope has a myriad of different functions.
This afternoon, I was thumbing through an old copy of QST from January of 2016, and came across an article on this kit. For those that may want to tackle this project at a later date on your own, it provides a good primer.
Also, the scope requires a 9v power source. There is a schematic at the end of this article for a 12v to 9v regulated power supply.