Common Faults in FM and TV Transmitters and Proven Prevention Methods for Reducing Recurring Failures and Improving Operational Broadcast Performance

Reliable broadcast transmission is essential for public information, education, and emergency communication, yet FM and television transmitter systems continue to experience recurring operational faults that degrade service quality and reduce coverage reliability. This study investigates common faults affecting FM and TV transmitters and evaluates proven prevention methods for reducing repeat failures and improving operational broadcast performance. The work is motivated by persistent field problems such as RF power amplifier (PA) overheating and premature failure, protection trips caused by high voltage standing wave ratio (VSWR), antenna and feeder system detuning, power-supply instability, and, in digital television systems, degradation of modulation error ratio (MER) and elevation of bit error rate (BER) leading to receiver lock loss and pixelation. Using maintenance records, performance measurements, and engineering benchmarks, the study analyzes fault mechanisms across both analog FM and DVB-T2 television transmission chains. For FM transmitters, empirical observations show that PA failures correlate strongly with sustained junction temperatures above 150 °C, reflected power levels exceeding 5 % of forward power (VSWR > 1.5:1), and bias drift beyond manufacturer tolerance limits. Preventive actions such as periodic bias verification, thermal-path maintenance, fan and filter replacement, and routine return-loss measurements reduced unplanned FM transmitter outages by approximately 35 % over a one-year operational period. Antenna and feeder inspections combined with vector network analyzer (VNA) trending enabled early detection of impedance drift, preventing secondary PA damage. For TV transmitters, particularly DVB-T2 systems, performance analysis shows that acceptable radiated power alone is insufficient to guarantee service quality. Measured MER values below 25 dB and post-FEC BER above 10⁻⁶ were consistently associated with coverage complaints, even when RF output power was nominal. Preventive methods integrating RF maintenance with digital-layer verification such as scheduled constellation analysis, shoulder emission monitoring, clock stability checks, and controlled exciter configuration management improved MER stability by 3–5 dB and reduced recurring service impairments by nearly 40 %. The findings demonstrate that transmitter faults are rarely random events but evolve from measurable electrical, thermal, and configuration-related stressors. A prevention framework that combines measurement-driven maintenance, condition-based interventions, and disciplined configuration governance is shown to significantly enhance broadcast continuity, regulatory compliance, and overall system resilience.