Hollow State Design, 3rd Edition

Grayson Evan (KJ7UM) has released his new 3rd edition of this very popular book, it’s now 57 pages larger than the first version with all-new chapters on mixers, power tubes, tube-type power amplifiers, and many updates and additions to all the chapters. Especially enjoyable are the new sections, busting myths about tubes, and a useful timeline of electron tube production. All together, there are now 17 chapters.
Other chapters are about oscillator design, covering 5 important oscillator configurations. They give in-depth information on selecting, building, and testing oscillators. This is information useful to experienced technicians and is also great for newcomers to the art of vacuum tube design. The oscillator design information has been collected from many sources and gives everything you would need in one location.

“Hollow State Design” is a unique book that all about rediscovering the fun and magic of building electronic circuits with vacuum tubes—or “thermatrons,” as the author prefers to call them!

Recreating information once thought to be lost or spread over many obscure volumes, this excellent new book contains everything you could ever possibly need to know about the art and science of vacuum tube design and circuit construction.

There is nothing else in print today that compares with “Hollow State Design!”

It pulls together, in one easy-to-read book, thermatron types and their characteristics, thermatron homebrew techniques, and practical how-to design of audio and RF triode and pentode circuits.

The book is quality printed on 333 pages, standard 8.5” x 11″ in size, and is packed with hundreds of photos, schematics, diagrams, plus charts and formulas that are essential when working with electron tube technology in the 21st Century. There are no “fuzzy” or blurred photos in the printing, everything is clear and sharp, very easy to read.

The author, Grayson Evans has been licensed since 1962 and grew up on thermatrons. He spent 40 years in the professional electronics industry, and is now bored to death with solid-state projects!


Available on backorder


Additional information

Weight48 oz
Dimensions12 × 8 × 3 in