Computer leads
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Computer leads
I have noticed that many leads for computers and peripherals have small cylindrical protruberances coming out of one end.
Does any one know the function of these cylinders?
Does any one know the function of these cylinders?
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- Posts: 17206
- Joined: Sat May 06, 2006 1:00 am
They're ferrite cores used to absorb high frequency electromagnetic radiation. They should be at the end of the cable that produces the signal.
They didn't need to be used in the old days of EGA and VGA but todays high resolution video signals need them to meet current EMC regulations.
The cables work perfectly alright without them but you may notice ghosting on either your monitor or any other visual device nearby (TV, second monitor) if you use old cables without them.
(From someone who's had to fit and tune far too many of them in his daily work!)
They didn't need to be used in the old days of EGA and VGA but todays high resolution video signals need them to meet current EMC regulations.
The cables work perfectly alright without them but you may notice ghosting on either your monitor or any other visual device nearby (TV, second monitor) if you use old cables without them.
(From someone who's had to fit and tune far too many of them in his daily work!)
Last edited by Woodles on Tue Jul 13, 2010 11:21 am, edited 1 time in total.
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- Active UBT Contributor 10+ yrs
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Although not quite on the same topic, i think from previous but limited experience some higher quality cables (for example network cables) have a built in shielding which looks a bit like tinfoil foil. This also helps to also protect them from electromagnetic interference from known problematic devices such as fluorescent lighting, or high powered electric cables that touch or are near to the cable which can cause interference.
The shield on the back of the PC (also known as the I/O shield which covers all the main ports such as network, printer, mouse, keyboard etc) also helps reduce electromagnetic interference to the internals of a PC by acting as a grounding device (to the outside of the PC case), as well as a protective cover.
Just in case anyone was interesting in learning something new! (I think that's right.. )
The shield on the back of the PC (also known as the I/O shield which covers all the main ports such as network, printer, mouse, keyboard etc) also helps reduce electromagnetic interference to the internals of a PC by acting as a grounding device (to the outside of the PC case), as well as a protective cover.
Just in case anyone was interesting in learning something new! (I think that's right.. )
Quite right Ben. Any cable with high frequency signals travelling down them should be screened but all it does is keep the noise inside the cable and prevent it radiating out and interfering with anything else. It's still present at the other end. The ferrite cores actually absorb the radiation (it gets converted into magnetic energy) so nothing unexpected comes out of the end.
(Sorry, I'm a physics guy, not biology)
Because we can! :P"Why do men have nipples"
(Sorry, I'm a physics guy, not biology)
UBT - bobuk wrote:To: Dr.Woodles
"Why do men have nipples"
Waiting Wolverhampton
b.
Since you asked. I saught an answer:
"The answer is that as embryos men and women have similar tissues and body parts. If anything the embryo follows a 'female template'. That is why nipples are present in both sexes. It is the effect of the genes, the Y chromosome and the hormone testosterone that brings about the changes and masculinises the embryo."
Which ties in quite nicley with what my sister said to me a while back as she was studying the subject.
Ah presumption is the mother of all evils :lol: I got the quote from another website, but referenced my younger sibling who had mentioned it to me a while ago Who as you quite rightly say has more sense than me! :lol:hgblade wrote:melter65 wrote:Yes, but he was quoting his sister - presumably older and wiser!! :lol: