Trouble getting clean signal with fiber optic setup

[kasuo]

Hey all, I’m working on a project and trying to understand fiber optic cable types. I tried setting up a short run but I’m getting signal loss after a few meters. Do I need single-mode for this, or did I mess up the connectors?

 

[davidgcet]

you need fiber that matches your optics. so i you have SM optics then you need SM fiber. if you have multimode optics, usually rated for like 300 meters or so max distance, then you need multimode fiber. also it is possible you broke the strand internally. how are you determining you lose light after a few meters? do you have an OTDR or a VFL? the first one is expensive but a VFL can be bought on Amazon for less than 30.00 plus an adapter or 2 to fit your connectors. if this is a duplex cable with 2 fibers, it has to roll end to end. port A on a SFP is always TX and port B is always RX so the connector has to roll A to B from one end to the other or both optics put light on the same fiber. Also you cannot mix SFP types between ends of the fiber. so if you have a 10km SM optic you can't have a MM sfp on the other.

 

[KE5MC]

Years ago I worked with HP's "low-end" fiber kit. One step was to dress or "polish" the fiber strand once crimped into the simple plastic housing. The purpose was to make sure the surface of the fiber was "flat/smooth" and at right angle to the axis of the strand. Maybe that will help...
Mike

P.S. It was single mode cable fairly inexpensive at the time. Moving async data a few feet between "black box & red box" configuration.

 

[kasuo]

Thanks for the tips, they helped me realize I was mixing up single-mode and multimode and messed up the splice. I came across a short guide on fiber-optic cable that explained the basics.