The Historian
Tom Marcotte, N5OFF, is one of the most important historical researchers in the R-390 community. For years, he has been diligently amassing production data — contract numbers, manufacturers, quantities, and serial number ranges — for the entire R-390 family of receivers. His meticulous research, conducted in partnership with Les Locklear and Wally Chambers K5OP, created the definitive record of who built these receivers, when, and in what quantities.
Tom’s work goes far beyond compiling spreadsheets. He collaborated directly with Les Locklear on the landmark “R-390A/URR Order Number List” articles published in Electric Radio and reprinted in the Hollow State Newsletter, providing the data backbone that made the articles possible. His production data also enabled Randy Stout’s “Spotter’s Guide” — a visual identification tool for recognizing different manufacturer variants from photographs.
Saving the Signal Corps Drawings
Perhaps Tom’s single most consequential act of preservation occurred in 1998, when he obtained the complete set of R-390A engineering drawings from Fort Monmouth on CD — over 1,000 original Signal Corps manufacturing drawings totaling 108 megabytes. He distributed copies to several trusted people in the community, ensuring this irreplaceable documentation would survive.
When Tom brought this archive to the R-390 reflector’s attention in August 2024, it triggered a major preservation effort. Larry Haney recognized the drawings should be hosted on r-390a.net, and Nick England K4NYW undertook the painstaking work of converting the files from a defunct government image viewer format into indexed, searchable PDFs.
“Many thanks to Tom for making this available.” — Nick England, K4NYW, upon posting the converted drawings to navy-radio.com
Technical Contributor
Tom also obtained and cleaned up the original MIL-R-13947B specification document for the R-390A (with Al Tirevold, WA0HQQ) and placed it on the r-390a.net website. He produced replacement nameplates that allowed restorers to properly identify receivers that had lost their original identification tags during decades of military service. He remains active on the R-390 reflector, contributing practical knowledge on topics from R-725 IF deck conversions to historical identification questions.
Key Contributions
- R-390A production data research — contract numbers, manufacturers, quantities, and serial ranges
- Preserved 1,000+ Signal Corps engineering drawings from Fort Monmouth (1998)
- Co-researcher on the R-390A/URR Order Number List series with Les Locklear
- Obtained and cleaned MIL-R-13947B specification with Al Tirevold
- Produced replacement nameplates for tag-swapped receivers
- Contributor to the Y2K Manual and R-390 Reflector archives
- Enabled the R-390A Spotter’s Guide through production data
Boatanchor Legends Tribute Series • vk6ada.com.au
Mike Peace VK6ADA / r-390a.net Administrator
Compiled March 2026 from the Hollow State Newsletter, R-390 Reflector Archives, and r-390a.net FAQ