Don Heywood earned his reputation in the R-390 community through deep, practical expertise with the original R-390 — the non-A variant that, while less widely collected than its successor, is regarded by many experienced operators as the superior receiver. Based in South Carolina, Don became one of the community’s trusted authorities on R-390 non-A restoration and repair, recommended by name when fellow enthusiasts needed work done on these complex receivers.

The Non-A Specialist

The original R-390, designed by Collins Radio in the early 1950s, is a substantially different receiver from the R-390A that replaced it. Where the R-390A used mechanical filters to achieve selectivity, the R-390 employed hand-wound LC filter circuits — a design approach that many operators describe as producing smoother, more natural audio. The trade-off was greater mechanical complexity, higher manufacturing cost, and a receiver that demanded more skill to maintain and restore properly.

Don’s specialization in the R-390 non-A placed him in a relatively small circle of practitioners. The receiver’s complexity and relative scarcity — far fewer R-390 non-A units survive compared to the R-390A — meant that the pool of people with genuine hands-on expertise was always limited. Those who developed that expertise became valuable resources for the community, and Don was among the most respected.

A Trusted Restorer

Les Locklear, himself a well-known figure in the R-390 community, recommended Don by name for R-390 non-A repair and restoration work. This kind of peer endorsement carries significant weight in a community where the cost of a botched restoration can be measured in irreplaceable parts and diminished receiver performance. The R-390 non-A, with its hand-wound filters and precision mechanical assemblies, is not a forgiving platform for inexperienced work.

Don’s active participation on the R-390 reflector mailing list provided a consistent stream of technical guidance for other non-A owners and enthusiasts. His posts addressed the specific challenges of non-A maintenance — from filter alignment procedures to the mechanical intricacies that distinguish the original design from its more widely known successor. For the subset of the community focused on the non-A, Don’s contributions were essential reading.

Preserving the Original Design

The R-390 non-A represents the pinnacle of Collins’ original design vision for the 51J series lineage — a receiver built without compromise to cost or complexity. Maintaining and restoring these receivers requires not just electronic skill but an understanding of precision mechanical systems and the design philosophy that produced them. Don’s work helped ensure that the knowledge needed to keep these receivers operating would not be lost as the original generation of military technicians who maintained them in service passed from the scene.

In a community where the R-390A dominates discussion and attention, advocates for the original R-390 serve an important role in preserving awareness of the full Collins military receiver legacy. Don’s expertise and willingness to share it contributed directly to the survival of knowledge that might otherwise have been lost to the hobby.