Welcome to the National Cryptologic Museum Foundation. The NCMF directly supports the National Cryptologic Museum (NCM), the first public museum in the U.S. Intelligence Community.

  • ...The nation’s brightest young minds to consider careers in STEM and cyber related fields

  • ...Robust dialog with the American public on cyber policy, technology, and privacy

  • ...Those who “served in silence” with valor and distinction, especially those who gave their lives in service

Did you know?

Polish mathematicians & code breakers made the first breakthroughs against Nazi Germany's Enigma code.......

"Rebuilding a Piece of the First Digital Voice Scrambler" by Jon D. Paul for IEEE Spectrum

"Rebuilding a Piece of the First Digital Voice Scrambler" by Jon D. Paul for IEEE Spectrum

If you are a fan of the unbreakable SIGSALY - you will definitely find the article (linked below) by scientist/inventor Jon D. Paul very interesting. After 20 years of researching digital technology and digital media, especially the SIGSALY, Mr. Paul explored the process of recreating a key component of the SIGSALY - the quantizer, using vintage parts. SIGSALY scrambled voices using a one-time random digital encryption key, but before the digital key could be applied, the quantizer converted the speaker's voice from analog to digital.

*Thank you to our friends on Twitter for alerting us to this excellent article!

About the Author
Jon D. Paul has been an EE and inventor since 1968, focusing on real-time signal processing, audio, cinema, telecommunications, and power conversion. He is an expert on cipher machines, speech encryption, and the history of technology. Paul is a member of the Association des Réservistes du Chiffre et de la Sécurité de l’Information (Association of Reservists of the Ciphers and Security of Information), frequently contributing to museum exhibitions and technical conferences in France.

The beginning of the article is included below. Please read the full article online via spectrum.ieee.org where you can also see photos and diagrams provided by Mr. Paul.

"Rebuilding a Piece of the First Digital Voice Scrambler:" This 1943 analog-to-digital converter helped make an unbreakable code - for IEEE Spectrum
by Jon D. Paul

In the years before World War II, German intelligence could decode band-scrambled U.S. radiotelephone conferences. After Pearl Harbor, an unbreakable speech scrambler was developed with top priority, and by 1943, it was deployed. Known as SIGSALY, the device pioneered many advances critical to modern digital media technologies, including spread-spectrum communications and the first use of pulse-code modulation (PCM) to transmit speech.

SIGSALY was top secret, so even today information about the details of its construction are hard to come by. I’ve spent 20 years researching the history of digital technology and digital media, especially SIGSALY. I searched IEEE and U.S. National Security Agency (NSA) journals, and Bell Telephone Laboratories patents. Finally, I found Lieut. Donald Mehl, a WWII SIGSALY technician, who gave me invaluable assistance. In 2015, I realized that it might be possible to re-create a key element of SIGSALY—the quantizer—using vintage parts....... READ THE FULL ARTICLE VIA IEEE.ORG


On This Day In History


  • In July 1993, the National Cryptologic Museum was first opened to NSA employees and their families, and to other members of the Intelligence Community. This photo is of the main exhibit room as it appeared in July 1993 - courtesy of former curator Jack Ingram.

About Us

The NCMF directly supports the National Cryptologic Museum (NCM), the first public museum in the U.S. Intelligence Community. We think you will agree it is truly a "museum like no other."

Located adjacent to the National Security Agency (NSA) in Maryland, the NCM houses a priceless collection of artifacts that represent our Nation's history in code making and code breaking, as well as a world class library of cryptologic media. The NCMF acquires the best artifacts for the NCM and supports new educational and interactive exhibits.

The NCMF provides exceptional cryptologic programs throughout the year, encourages young minds to explore cryptology and innovation through valued awards, and hosts educational, cryptology-related exhibits at various community events.

As part of the Foundation's partnership with NSA to build the Cyber Center for Education and Innovation - Home of the National Cryptologic Museum (CCEI-NCM), the NCMF also serves as a leader in the field of cybersecurity - striving to provide the best in educational resources and programs.

The NCMF and NCM share a joint three-fold mission to Educate, Stimulate, and Commemorate. Learn more about our MISSION.