Description of structures, schematic diagrams and methods of their calculation for some units are given. The interests of novice and qualified radio amateurs are taken into account. DOSAAF educational organizations • Automatic telegraph key with adjustable dash duration • Measuring equipment • Active probes with low input capacity • Tester for digital microcircuits • Sound reproduction and radio reception • Digital reverberator • Medium-wave direct amplification receiver • Digital equipment and automation in everyday life • Multifunctional automatic light effects • Electronic clock with calendar and alarm • Power supplies • Chip power supply • Connection of decimeter selectors to black and white TVs.