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Signode
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Join Date: Aug 2007
Location: Lahore
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A Question About Communication Cables

04/20/2014 5:31 AM

Dear Friends;

please see in the below image, there is a cylindrical type something which can be seen with all kind of signal/communication/VGA cables. Can anybody explain about the reason of this thing?

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JohnDG
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#1

Re: A question about communication cables

04/20/2014 7:09 AM

It's a blob of ferrite, intended to stop RF noise getting from the PC into the cable (which would then act as an aerial to transmit EMI).

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redfred
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#4
In reply to #1

Re: A question about communication cables

04/20/2014 10:24 AM

Exactly. This ferrite core increases the impedance of the higher frequencies trying to travel on the shield. This minimizes the RF radiation being coupled into free space.

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lyn
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#2

Re: A question about communication cables

04/20/2014 9:32 AM

See "EMI choke".
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Fredski
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#3

Re: A question about communication cables

04/20/2014 10:14 AM

think of it as a filter for your electrical suppy
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niftyniall
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#5

Re: A Question About Communication Cables

04/21/2014 1:43 AM

Google Ferrite Choke

The ferrite choke in your picture is also frequently known as a Ferrite bead

They work well, especially in noisy electrical environments. They are fragile, and practically useless when broken. i.e, throwing cables around on concrete floors will damage them, the nice thing is they can be replaced by clamp on types.

In some environments it helps to be able slide the device along the cable to null out / tune out, the noise.

Cheers

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merc600sec
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#6

Re: A Question About Communication Cables

04/21/2014 5:54 AM

Are you from off world, a visitor to my planet?? Mr POWER user you dont recognise a RF choke. Get back to your Abucus and stop trying to involve yourself in the modern world, Jeez a look at cable packaging or a simple google search would have told you. Oh and they are not edible burnable or to be used for fishing weights ..Caveman..

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North of 60
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#7
In reply to #6

Re: A Question About Communication Cables

04/21/2014 11:20 AM

Geese... who woke you up on the wrong side of the bed?

I see no value in the tone of your reply at all. This is a discussion forum, the OP posted a well crafted question that, while appearing to be coming from a Luddite (in your estimation), it was a valid question and certainly did not deserve your clear disdain.

One has to wonder who is the "caveman".

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Signode
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#8
In reply to #7

Re: A Question About Communication Cables

04/28/2014 7:03 AM

Understood. Thanks to all for their inputs.

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Users who posted comments:

Fredski (1); JohnDG (1); lyn (1); merc600sec (1); niftyniall (1); North of 60 (1); redfred (1); Signode (1)

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