# Telecommunication



## Speedy Petey (Jan 10, 2007)

I'm not sure. What are some of the other questions on the test?


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## Jordan De Armas (Jan 28, 2009)

*Telecommunications*

What is the inductance reactance of 40hertz and 400hertz


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## Speedy Petey (Jan 10, 2007)

Nope, I got nuthin'. Sorry.


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## Speedy Petey (Jan 10, 2007)

Is there any chance you could study to find the answers?


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## sherman (Sep 29, 2008)

Can you make this a multiple choice??


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## Trimix-leccy (Dec 4, 2007)

http://ourworld.compuserve.com/homepages/Bill_Bowden/XLC.htm

But only if you know the inductance in the first place

Xl = wL

w = 2 x Pi x f

Well it was 30+ years ago when I used to care:whistling2:


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## hbiss (Mar 1, 2008)

2w in x .25= 0.5w

Formula for power ratio is:

10 x (log P1/P2) 

So

10 x (log 2/.5)= -6.02db

Simple rule of thumb for you to remember is 1/4 the power is -6db. That's what they are asking. 

-Hal


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## cdnelectrician (Mar 14, 2008)

I am sorry if I am out of line here...but PLEASE improve your grammar, spelling and punctuation when posting. We are all guilty of the above, but this is bad! Give us some backround on your problem and we will help!


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## hbiss (Mar 1, 2008)

I agree. I had to read tht several times myself. This is what he appeared to say:

A 2 watt signal is is input (to a pair of wire, device etc.) and the output is .25 attenuation. What is the decibel loss? 

In other words what is a power loss of .25 (or one-fourth) expressed in db. 

-Hal


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