## Technical Overview of CA-RSPNFBA004 The **CA-RSPNFBA004** is a specialized RF (Radio Frequency) coaxial cable assembly. It is primarily used to bridge connections between cellular devices (like gateways or boosters) and external antennas. ### 1. Component Breakdown | Component | Specification | Description | | :--- | :--- | :--- | | **Connector A** | RP-SMA Plug (Male) | Reverse Polarity SMA. Common in Wi-Fi and specialized cellular equipment. | | **Connector B** | N-Type Female | A rugged, threaded, weatherproof connector used for outdoor antennas. | | **Cable Type** | LMR-195 (or equivalent) | A low-loss flexible communications coaxial cable. | | **Length** | 4 Feet | Standard short-run length to minimize signal attenuation. | --- ### 2. Electronic Characteristics The performance of this part is defined by its ability to transmit high-frequency signals with minimal interference. #### Impedance * **50 Ohms:** This is the standard impedance for RF communications. It ensures maximum power transfer and minimum signal reflection between the device and the antenna. #### Frequency Range * Typically rated for **DC to 6 GHz**. This covers most commercial wireless bands, including: * 4G LTE / 5G Sub-6 GHz * Wi-Fi (2.4 GHz and 5 GHz) * LoRaWAN / Helium Network (915 MHz) #### Signal Loss (Attenuation) The LMR-195 cable inside this assembly has specific loss profiles. At 4 feet, the loss is negligible but measurable: * **900 MHz:** ~0.4 dB loss * **2500 MHz:** ~0.7 dB loss * **5800 MHz:** ~1.1 dB loss --- ### 3. Physical Construction The "electronic" integrity of the cable is protected by its physical layers: 1. **Center Conductor:** Usually Solid Bare Copper or Copper Clad Aluminum (CCA). This carries the actual electrical signal. 2. **Dielectric:** Foam Polyethylene (PE). This acts as an insulator and maintains the spacing between the conductor and shield to ensure 50 Ohm impedance. 3. **Shielding:** Double shielded (Aluminum foil + Tinned Copper Braid). This prevents **EMI (Electromagnetic Interference)** from leaking out or entering the signal path. 4. **Jacket:** Black PE or PVC. Provides UV protection and physical durability. --- ### 4. Common Applications * **Helium Miners / LoRa Nodes:** Connecting a hotspot (RP-SMA) to a large outdoor fiberglass antenna (N-Type). * **Industrial Modems:** Linking a Cradlepoint or Sierra Wireless gateway to an external rooftop antenna. * **Wi-Fi Bridging:** Extending Wi-Fi signals using high-gain directional antennas.