Reliable timing components, in stock locally
When your circuit depends on precise timing - from microcontroller clocks to RF front-ends and RTC modules - sourcing the right crystal, oscillator or resonator matters. Communica keeps a broad range of frequency control parts in Southern Africa so you can avoid long lead times and get back to prototyping or production quickly. Our range covers through-hole and SMD package types, common clock frequencies, temperature-compensated and MEMS oscillators from known manufacturers carried across our inventory.
Why choose local stock over long import delays
Local availability reduces downtime for coursework, lab builds and production runs. Collect from our Samrand head office or visit branches in Pretoria CBD and Cape Town to inspect parts in person. For purchase orders and VAT invoicing - important for university departments and procurement teams - we provide formal quotes and account services.
Specifications that matter when selecting timing parts
Focus on frequency tolerance, stability over temperature, load capacitance for crystals, output type and drive level for oscillators. Below is a compact comparison to quickly match part type to application needs.
| Type | Typical use | Key specs |
|---|---|---|
| Quartz Crystal | Microcontroller clocks, real-time clocks | Frequency, load C, ESR, package (HC-49/SMD) |
| Oscillator (VCXO/TCXO) | Precision clocks, comms, timing sync | Output (CMOS/TTL), stability, phase noise |
| Resonator | Cost-sensitive clocking, microcontrollers | Lower precision, built-in capacitors, size |
Common frequency selection rules
Start with the controller or IC datasheet recommended clock. For microcontrollers, 8 MHz, 12 MHz and 16 MHz crystals are common; RTC modules typically use 32.768 kHz crystals. When substituting, match load capacitance and ensure the ESR is within the MCU’s allowed range.
Practical compatibility check (quick formula)
Estimate total load capacitance seen by the crystal: Ct = (C1 * C2) / (C1 + C2) + Cstray. Choose C1 and C2 so Ct matches the crystal’s specified load capacitance (Cload). Typical Cstray is 2-5 pF for PCB and pin parasitics.
Explore our stocked categories to compare part families and footprints: Shop by Category and see all inventory with datasheets on the All Products index.
