The two tools every fiber tech carries: a power meter to measure how much light arrives, and a visual fault locator to light up faults you can see with your own eyes.
A power meter reads optical power in dBm — a logarithmic scale where 0 dBm is 1 milliwatt. Because it’s logarithmic, every −3 dB is roughly half the power. Techs use it to check a transmitter’s output and confirm a receiver is getting enough light.
To measure a link’s loss, put a stable light source at one end and a power meter at the other. First take a reference across a short reference cord, then measure the real link. The difference, in dB, is the link’s insertion loss — the number acceptance tests live or die by.
A visual fault locator injects a bright red 650 nm laser into the fiber. At a break, a tight bend, a bad splice or a poorly seated connector, the light escapes and glows red right through the jacket — so you can find the fault by eye over the last few kilometres, no instrument reading required.
The Fiber Optic Lab turns these concepts into hands-on instruments you can practise safely — no fragile fiber, no costly gear. Log in to the suite to try them.
Confidential — prototype under development. This prototype and all associated content are the proprietary and confidential property of Daw Alfada, shared solely for authorized technical review. Any unauthorized copying, redistribution, reverse engineering, or commercial use — in whole or in part — is strictly prohibited. © 2026 Daw Alfada. All rights reserved.
