This book, by Wilhelm Flicke, was written shortly after WW2. Flicke was present at the beginning of sigint and was part of it, for the German side, from WW1 till the end of WW2. He wrote his book from memory and notes he kept, and before he got it published, the US government bought the rights to it to prohibit its emergence upon the world. The NSA inherited the copyright and kept it for decades, just recently deciding to allow it to be downloaded. It's an excellent work any radio/sigint buff will enjoy.
https://www.nsa.gov/public_info/_fil...1019080017.pdf
https://www.nsa.gov/public_info/_fil...1019080017.pdf
Flicke's work covers WW1 to the end of WW2, with the inter war period as well.
This work, The American Black Chamber, by Herbert Yardley, has a similar story.
http://marshallfoundation.org/librar...tated-digital/
Yardley, an American, was employed first by the US Dept of State as a code tech prior to WW1, and then by the US Army in the same profession. When he was let go by the fedgov he decided to write about what he had been up to all these years, the fedgov tried to stop him from publishing to no avail. This copy on pdf has notes by William Friedman, who is a world famous cryptographer in his own right (he and his team, who was not let go by the fedgov, broke the Japanese "Purple" code), making it an even better read.
I hope you guys enjoy them as much as I have, and my condolences if they have been previously linked.
https://www.nsa.gov/public_info/_fil...1019080017.pdf
https://www.nsa.gov/public_info/_fil...1019080017.pdf
Flicke's work covers WW1 to the end of WW2, with the inter war period as well.
This work, The American Black Chamber, by Herbert Yardley, has a similar story.
http://marshallfoundation.org/librar...tated-digital/
Yardley, an American, was employed first by the US Dept of State as a code tech prior to WW1, and then by the US Army in the same profession. When he was let go by the fedgov he decided to write about what he had been up to all these years, the fedgov tried to stop him from publishing to no avail. This copy on pdf has notes by William Friedman, who is a world famous cryptographer in his own right (he and his team, who was not let go by the fedgov, broke the Japanese "Purple" code), making it an even better read.
I hope you guys enjoy them as much as I have, and my condolences if they have been previously linked.