EF Johnson 23-2569-003 Duplex Filter RF Electronic Component Waseca MN

EF Johnson 23-2569-003 Duplex Filter RF Electronic Component Waseca MN

The EF Johnson 23-2569-003 is a duplex filter — an RF passive component designed to allow two signals to share a common antenna or transmission path by separating transmit and receive frequencies into distinct signal paths. It is housed in a compact, fully shielded metal enclosure with two white wire leads for circuit connection. This example is new old stock, pulled directly from its original E.F. Johnson Company box labeled "Electronic Components," made in Waseca, Minnesota, USA.

Specifications & What's Included

• Manufacturer: E.F. Johnson Company, Waseca, Minnesota, USA
• Part Number: 23-2569-003
• Type: Duplex Filter (RF passive component)
• Housing: Shielded metal can enclosure, silver/nickel finish
• Termination: Two wire leads (white, bare tinned ends)
• Mounting: Four rubber feet on base; mounting holes on base panel
• Connection posts: Two coaxial-style threaded studs visible on base face
• Condition: New old stock — unused, in original branded box
• Includes: Filter unit and original E.F. Johnson Company box

Applications

Duplex filters are used in RF and radio communications systems to combine or separate transmit and receive signals, allowing a single antenna to handle both directions simultaneously without interference between paths. E.F. Johnson Company was a well-regarded American manufacturer of radio communications equipment and electronic components from the mid-20th century, based in Waseca, Minnesota. Their components were widely used in amateur radio (ham radio), commercial two-way radio, and industrial communications applications. A component like the 23-2569-003 would have been intended for use in radio transceivers, repeater systems, or similar RF assemblies of that era. New old stock E.F. Johnson components are sought after by vintage radio restorers, ham radio builders, and electronics hobbyists working on period-correct equipment.