简介

Frequency Counter+ precisely measures the dominant frequency of any sound in Hz using your iPhone's microphone. Detect electrical hum (50/60Hz), measure fan RPM from sound, and analyze resonant frequencies. A digital multimeter-style display shows the frequency in large, clear numbers with instant Hz-to-RPM conversion. Key Features: - Precise Hz frequency measurement - Large digital multimeter-style display - Automatic 50/60Hz electrical hum detection - Instant Hz to RPM conversion - Musical note reference display - Measurement history and trend graph - Adjustable measurement sensitivity Perfect for electricians, HVAC technicians, audio engineers, and industrial diagnostics.