Development of a Low-Cost Microcontroller-Based RLC Meter for Real-Time Waveform Analysis

Publication Details

Publication Date

10/11/2026

Volume / Issue

Vol 1, Issue 6 (2026)

Article No.

055

Journal

British Journal of Contemporary Research

DOI

https://doi.org/10.67693/BJCR-Y2BGT6G9

Received

23 Oct 2026

Views

21

Downloads

11

Abstract

This paper presents the design, fabrication and performance evaluation of a low-cost, locally fabricated digital RLC meter integrated with an oscilloscope interface for real-time waveform analysis. The instrument uses an Arduino Pro Mini (ATmega328P) microcontroller with its built-in 10-bit analogue-to-digital converter (ADC) to measure resistance, inductance and capacitance using voltage-divider and oscillator-frequency techniques. The system incorporates analogue signal conditioning, a three-way component-selection switch and a 2 × 16-character LCD for display of measured values, while the oscilloscope interface allows observation of voltage waveforms and phase relationships during component testing. The prototype was evaluated against seven resistors, eight capacitors and eight inductors of known nominal value (mean of three readings each) and against 17 further components of unknown value. Agreement with nominal values gave a mean absolute percentage error (MAPE) of 3.12 % for resistance (maximum 8.33%), 0.62% for capacitance (maximum 1.00 %) and 1.97 % for inductance (maximum 4.88%); all capacitors and inductors fell within their stated tolerances, and six of seven resistors fell within ± 5 %. Resistance was read systematically low by a near-constant offset (mean bias −3.12 %, 95% CI −5.49 % to −0.75%, p = 0.018), while capacitance and inductance showed no statistically significant bias (p = 0.52 and 0.70 respectively). A theoretical uncertainty budget indicates that 10-bit ADC quantisation together with a ±1% reference resistor limits resistance measurement to roughly ±1.2 % (k = 2) at mid-scale, which bounds how far the systematic offset can be removed by calibration alone. Oscilloscope waveforms and time-domain phase traces were obtained for each component type. The prototype was fabricated at a materials cost of approximately ($16.65, ~94% lower than $300–$500 commercial handheld LCR meters), while providing measurement agreement suitable for educational, laboratory and field use.

License

This article is published under the Creative Commons Attribution 4.0 International License . Free to read, share, and adapt with attribution.