This Rhythm generator design was published in the Practical Electronics January and February 1978 magazine. It is a great DIY project which will learn you about electronic circuits for drum sound generation and a pattern sequencer.
Note: below the images we have included a link to youtube for a demo of this Rhythm generator, the original articles in Practical Electronics as separate images and as PDF file.
The project was also marketed by Watford Electronics, who sold this unit in KIT form, named ‘Mark II Watford Electronics Rhythm Generator). The following image is taken from the Watford Electronics 1978 Catalogue:
Below is a Youtube video demo-ing the Watford Mark I rhythm generator, which was a precursor machine.