The Eddystone E2075 is a broadcast audio fail and changeover unit that provides automatic or manual transmitter and drive switching with flexible RF routing and remote control for resilient FM services.
The Eddystone E2075 Broadcast Audio Fail & Changeover Unit is designed to keep FM services on air by supervising main and reserve transmission paths and switching automatically when a fault or audio loss occurs. Mounted in a compact 1U rack chassis, the Eddystone E2075 combines internal RF changeover relays, audio monitoring, status sensing and remote control to give engineers a single point of management for redundant transmitter systems.
An internal relay board provides four 50 Ω TNC ports for Tx1, Tx2, antenna and dummy load, with a power handling capability of up to 200 W at 100 MHz, de‑rating to 100 W at 500 MHz. This allows direct switching of many low and medium power FM transmitters, while parallel control and monitoring outputs are available for external RF relays or switch-less combiners where higher power or wider frequency coverage is required. Eight tactile front-panel switches select operational mode, route transmitters to antenna or load and provide positive local control during maintenance or fault-finding.
A microcontroller-based control system with flash memory supervises status lines from two associated transmitters or drives and, in rebroadcast systems, up to two receivers. Internal option switches select analogue or digital status monitoring, define “good” level thresholds, set input/output polarities and adjust changeover delays so the Eddystone E2075 can be aligned with existing site practices. Comprehensive hardware and software watchdogs illuminate a CPU alarm LED and force a safe condition if any internal software fault occurs, avoiding misleading front-panel indications.
