The Professional Engineer
Roy Morgan, K1LKY (of Western Massachusetts, formerly at the National Institute of Standards and Technology), brought professional-grade engineering discipline to the R-390 community. His restoration guidelines for the R-390 (non-A) receiver became a foundational reference — a systematic, no-nonsense checklist that remains hosted at r-390.com and is still cited decades after it was written.
Roy’s restoration advice was characteristically direct and prioritized safety and longevity. His recommendations included applying forced-air cooling to the 6082 voltage regulator section, the critical warning never to unplug the PTO without understanding the consequences for B+ regulation, and the imperative to replace all 47-ohm cathode balancing resistors in the audio module and power supply.
“The following suggestions as to what should be done to the R-390 that you are restoring have been supplied by Roy Morgan. I support all of them.” — r-390.com, introducing Roy’s restoration checklist
PTO Linearization Research
Roy collaborated with José Gavilá (EB5AGV) on the challenging problem of PTO linearization — the painstaking process of adjusting the corrector stack compensators at each 25 kHz point to achieve maximum tuning accuracy across the full 1 MHz range. This cross-country collaboration pushed the boundaries of what hobbyists could achieve with PTO accuracy.
Community Watchdog
Roy also served as an important quality-control voice. His 2006 identification of significant errors in the “R-390 Cookbook” was described by Larry Haney as “quite alarming.” Larry eventually summarized Roy’s findings into a formal error document on r-390a.net, replacing the direct link to the Cookbook with a warning. This careful, critical review prevented countless newcomers from following dangerous or incorrect procedures.
Roy was an active reflector participant from at least 1997 through 2024, contributing on topics from squelch modifications and audio deck circuits to test equipment recommendations. His posts carried the authority of someone who understood both theoretical engineering and practical realities.
Key Contributions
- Definitive R-390 (non-A) restoration guidelines — the “Morgan List”
- PTO linearization research with José Gavilá EB5AGV
- Identification of critical errors in the R-390 Cookbook
- Audio deck modification guidance including diode load tap techniques
- Squelch circuit analysis and modification advice
- Professional RF engineering perspective from NIST background
- Over 25 years of active reflector contributions (1997–2024+)
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