Fiber Optic Notes

Fiber course day 2/ chapter 15

pre testing cables is important

fiber cable is immune to interference

ensure signal arrives to its destinations

optical power and signal loss are whatr you test for.

Optical power is the basic contiunity test

receiving end and transmitting end.

For multimode you need specific light source 850 nano meters 1300

same with single mode 1300 or 1550n

hardware dictates what you test on.

Optical power is the most basic of tests

lets us know light is going from point a to pt b

loss testing- use a light source, opposite end you use a power meter.

Decibels measures loss

rule of thumb- per meter if dealing with single mode. Most can lose is 1.5 decibles and multi mode

connectors should not lose more than .5

splices should not lose more than .3.

you can lose a little more.

Those are the only tests required.

Fiber optic power meter- measure s intensity of the signal being transmitted over a fiber optic cable.

The signal source is led or laser.

Led are for multi

laser are for single mode.

Led are less expensive

you need a light source and pwr meter.

Olts- optical loss test source

always test both ways

otdr- optical time domain reflectometer- long distance, finds faults in network. Not a tool to give loss value. Cannot give fault location in a local area netwk.

A test cord is called a launch cable.

Receiving cable.

Dead zone- first 100 ft

splice loss- always some loss

back refraction- light collect at break pt, and is reflected back.

Back scatter is light being sent back the opposite way

otdr- must have for out door installs

fiber microscope, - detects dirty crack or disabled connectors. Have build in light source.

Vfl- visual fault locator. - flash light. Sends light down cable- identifies specific fiber. And test contiuity,

test cable box, to save time. If light goes all the way through, you...