## Overview of the FTS-22-R The **FTS-22-R** is a high-precision, sub-miniature **Rubidium Atomic Oscillator** (often referred to as a Rubidium Frequency Standard). It is primarily designed for high-stability timing and frequency applications where a standard quartz oscillator is insufficient. --- ### Core Specifications Below are the primary electronic characteristics of the FTS-22-R: | Parameter | Specification | Note | | :--- | :--- | :--- | | **Output Frequency** | 10.0 MHz | Sine wave or HCMOS options | | **Short-Term Stability** | < 2x10⁻¹¹ (at 1s) | Excellent Allan Deviation | | **Phase Noise** | -145 dBc/Hz (at 100Hz) | Low noise floor | | **Supply Voltage** | 12 VDC to 15 VDC | Standard industrial range | | **Power Consumption** | ~10W (Steady State) | Higher during warm-up (~25W) | | **Aging Rate** | < 5x10⁻¹¹ per month | Long-term reliability | --- ### Key Electronic Components & Subsystems The FTS-22-R operates using a "physics package" integrated with control electronics: 1. **The Physics Package:** * **Rubidium Lamp:** A glass bulb filled with Rubidium gas, excited by RF to emit light. * **Resonance Cell:** Where the atomic transition occurs. * **Photodetector:** Measures the light intensity to detect the hyperfine transition (6.834 GHz). 2. **Servo Control Loop:** * An internal **VCXO (Voltage Controlled Crystal Oscillator)** provides the actual 10MHz output. * The electronics continuously compare the VCXO frequency to the atomic resonance. * An error signal is generated to "lock" the crystal to the rubidium transition. 3. **Interface Pins:** * **Frequency Adjust:** An analog input (or digital interface) to fine-tune the output frequency. * **Lock Monitor:** A digital output signal (High/Low) that indicates if the unit has successfully stabilized and locked to the atomic reference. --- ### Applications Because of its electronic precision, the FTS-22-R is used in: * **Telecommunications:** Synchronization of cellular base stations (LTE/5G). * **Test & Measurement:** External clock references for spectrum analyzers. * **Aerospace:** Precise timing for satellite ground stations. * **Calibration Labs:** As a secondary frequency standard. --- ### Comparison with Traditional Oscillators | Feature | Quartz (OCXO) | FTS-22-R (Rubidium) | | :--- | :--- | :--- | | **Accuracy** | Moderate | Very High | | **Warm-up Time** | Fast | Slow (approx. 5-10 mins) | | **Size** | Small | Large (Modular) | | **Drift** | Significant over time | Extremely low |