In this video I will show you how to operate the Optical Power Meter function of your cheap tester from Amazon. I know not everyone likes the super cheap knockoff, so I will link several brands you can look at and decide which one you like the look of. If you use any of these links it supports my channel and I benefit, but don't feel obligated to use them of course.

The Nofaya Tester in this video: https://amzn.to/3C77jhH
A Jonard Brand Tester: https://amzn.to/45z10Be
The Fluke Tester: https://amzn.to/45BfS1N
Another Cheap Knockoff: https://amzn.to/3WFWnkO
My favorite patch cords: https://amzn.to/3WDv9ew
All manner of couplers: https://amzn.to/3C2IzqW

I think once you see the prices you'll agree the cheapo is the way to go until you are making that government money.