Coaxial cable lightning surge protectors play a crucial role in safeguarding RF circuits from harmful surges and ensuring optimal signal transmission. They are designed to seamlessly allow the passage of desired RF signals with minimal loss or disturbance.
When an RF signal passes through a surge protector, it undergoes a combination of processes including transmission, reflection, and dissipation. Each of these factors significantly impacts the overall performance of the coaxial connector.
The critical RF performance parameters for consideration are:
- RF frequency range - protectors are physically designed to operate optimally within pre-specified frequency bands. Observing this becomes crucial to ensure impedance matching, proper attenuation characteristics, avoidance of resonance effects, and general compatibility with the RF system.
- Insertion loss - measured in decibels (dB) and represents the reduction in signal strength as it passes through the surge protector. High-quality coaxial surge protectors aim to keep the insertion loss as low as possible to maintain optimal signal transmission. Well-designed coaxial surge protectors can achieve insertion loss values as low as a fraction of a decibel (e.g., 0.1 dB or lower).

However, it's important to note that even small amounts of insertion loss can accumulate in complex RF systems with multiple connectors and components.
- Voltage standing wave ratio (VSWR) or return loss - quantifies the reflection of a signal back to the source.