We have had no changes in our fiber optic cable assembly production process, but the measured Insertion Loss (IL) and Return Loss (RL) values of our product aren’t as good as they were. Could there be something wrong with the measurement equipment?



Obviously something has changed. If it’s not the measurement equipment, then it must be either the product or the measurement setup. Over time the production process can become a familiar, perhaps boring, routine. Operators may become less meticulous in cleaning, use polishing film longer than appropriate, or even take shortcuts. Eventually this takes a toll and yield suffers.

Let’s suppose you’ve eliminated this possibility with a clean sweep of procedures and a reset to rigorous production guidelines. Yet the problem persists. A “gold-standard” product is useful at this stage – a “known-good” example of the best of your previous production, carefully kept, with very good IL and RL values recorded. Using your current rigorous procedures, re-measure this gold-standard product. It should still look good. If it doesn’t, read on …

I have written that IL and RL tests on a product cannot be made in isolation. (Read more on this topic here.) Remember, we are measuring connector loss, and the device under test (DUT) needs to be connected to a test cable (aka jumper cable, reference cable, or test lead). It’s important to note that the quality and condition of test cables have a direct bearing on the measured product’s IL and RL measurements.

READ THE FULL BLOG ARTICLE HERE: Test cables don’t last forever: How to assess quality, condition, usage limit, and replacement schedule







  Answered by AskFOC Technical Team April 17, 2019



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