Univox FSM: Digital Field Strength Meter for AFILS, User manual (UP_5-0142-1.0-EN)

Summary

Specifications and operating instructions for a digital loop meter, including a calibration tolerance at one reference level and frequency.

Key findings

• Page 8 specifies calibration accuracy of ±0.5 dB at 400 mA/m and 1 kHz. It gives 1 dB display resolution between -3 and +6 dB and between -29 and -20 dB; resolution and calibration accuracy are separate specifications.
• Page 8 identifies part number 401016 and gives high and low ranges of -18 to +8 dB and -44 to -18 dB relative to 0.4 A/m. It specifies RMS detection at 125 ms or a peak programme meter mode with a 3.5 ms rise time and a 1.7 s fall time for a 20 dB fall.
• Page 8 gives flat-response accuracy better than ±1 dB from 50 Hz to 10 kHz; A-weighted response is better than ±1 dB from 100 Hz to 10 kHz and ±2 dB from 25 Hz to 20 kHz.
• Page 4 recommends annual recalibration because accuracy can change with time, and a calibration check after the meter is dropped or damaged, followed by recalibration if needed.
• Page 5 describes the coil location and orientation, particularly for small counter and neck loops. It says the low range applies A-weighting and disables the flat-response option. Headphone monitoring works in both ranges and filter settings.
• Page 4 says a flashing blue range indicator means the batteries need replacing. Pages 6-7 ask users to define test points and listening heights, use the low range for background noise, use high range with flat response for field strength, and record the 100 Hz and 5 kHz readings relative to 1 kHz at each test point.

Limits

Manufacturer specifications, not an independent comparison or a measured uncertainty budget for a venue survey. The ±0.5 dB specification applies at the stated reference level and frequency. No publication date is printed; the URL upload directory is not treated as a publication date.

Read the original

univox.eu/wp-content/uploads/sites/2/2023/11/UP_5-0142-1.0-EN.pdf

Link checked 13 October 2026. We link to the original and do not host copies.

Cited in

• Which meters and apps measure loops and Auracast, and how accurate are they?Partly answered

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