This is the full, freely accessible PDF of David L. Heiserman's 1976 book How to Design & Build Your Own Custom TV Games. A foundational work from the early era of DIY video game engineering.
Originally published by TAB Books, this guide helped hobbyists understand the underlying electronics behind their televisions and game systems long before the home-console boom.
If you'd like to support ongoing preservation of David's work, consider a small donation to Free-Ed.