The **UM-5-R** refers to a specific type of **Quartz Crystal Resonator** used in electronic timing and frequency control circuits. The "UM" designation refers to a standard sub-miniature metal can package, while the "-5" indicates the height profile, and the "-R" typically signifies RoHS compliance or a specific taping/reeling specification. --- ### 1. Technical Specifications The UM-5-R is favored for its small footprint and high stability. Below are the typical technical parameters: | Parameter | Specification (Typical) | | :--- | :--- | | **Frequency Range** | 10 MHz to 200 MHz | | **Package Type** | Through-hole Metal Can (UM-5) | | **Height** | 6.0 mm (Approx.) | | **Load Capacitance** | 10pF, 20pF, or Series Resonance | | **Frequency Tolerance** | ±10 ppm to ±50 ppm | | **Operating Temperature** | -20°C to +70°C (Standard) | | **Drive Level** | 10µW to 100µW | --- ### 2. Physical Characteristics The UM-5 package is part of a family of "slim" vertical crystal units. * **Construction:** It consists of a quartz wafer mounted inside a hermetically sealed metal cylinder to protect it from environmental moisture and oxidation. * **Mounting:** It is a through-hole component with two wire leads protruding from the base. * **Dimensions:** It is significantly smaller than the older HC-49/U standards, making it ideal for compact radio equipment. --- ### 3. Key Applications Because of its precision and small size, the UM-5-R is commonly found in: * **Telecommunications:** Pagers, handheld radios, and wireless base stations. * **RF Circuits:** Used as a reference oscillator in frequency synthesizers. * **Consumer Electronics:** High-end audio equipment and specialized timing modules. --- ### 4. Circuit Symbol and Integration In a schematic, the UM-5-R is represented by the standard crystal symbol. It is usually paired with two "load capacitors" ($C_1$ and $C_2$) to create a stable oscillation loop with an IC. ```mermaid graph LR A[Inverter Input] --- B(Crystal UM-5-R) B --- C[Inverter Output] A --- D[Capacitor 1] C --- E[Capacitor 2] D --- F[Ground] E --- F ``` ---