The book "Diagnostics of digital PBX F 50/1000: methodical instructions for laboratory work on the course "Commutation Systems" by Sergey Mikhailovich Lapshin is an indispensable resource for students studying modern communication and telecommunications systems. With the rapid development of digital technologies, understanding of the principles of automatic telephone stations (ATS) is becoming increasingly relevant. This book offers a deep and systematic approach to the study of the diagnosis and maintenance of digital PBX, which makes it a valuable tool for future communication professionals. In the book, Lapshin shares not only theoretical foundations, but also practical aspects of working with digital PBX F 50/1000. Readers will be able to familiarize themselves with diagnostic methods that will help identify and eliminate malfunctions, as well as optimize the operation of systems. Each laboratory work is accompanied by clear instructions and recommendations, which allows students not only to absorb the material, but also to apply it in practice. This makes the book an ideal assistant for both students and teachers seeking quality teaching in the field of switching systems. Who can like this book? First of all, it is intended for students of technical universities studying in specialties related to information technology, telecommunications and electronics . However, interest in it can also be shown by practitioners working in the field of communications, as well as graduate students engaged in scientific research in this field. The book will be useful for those who want to deepen their knowledge of digital PBX and master the practical skills of their diagnosis and repair. The topics raised in the book cover a wide range of issues related to the functioning of digital PBX. Lapshin emphasizes the importance of diagnostics as an integral part of working with modern communication systems. It considers various methods that allow not only to identify faults, but also to predict possible problems, which is especially important in conditions of constant growth of information volumes and increasing load on networks. The book also addresses the issues of reliability and stability of systems, which is a key aspect in working with telecommunications technologies. The author's style is characterized by accessibility and clarity of presentation, which makes complex technical aspects understandable even for novice specialists. Sergey Mikhailovich Lapshin is an experienced teacher and practitioner who knows how to convey information to students . His other works are also devoted to telecommunications and communication systems, and they are popular with students and professionals. If you are looking for a book that will help you not only to master the theory, but also to gain practical skills in working with digital PBX, "Diagnostics of digital PBX F 50/1000" will become your reliable assistant. It will allow you to confidently step into the world of modern technology, learn how to diagnose and troubleshoot, and prepare you for a successful career in communications. Do not miss the opportunity to enrich your knowledge and skills with this unique guide!