HMC150: What do the Ferrite Cores do? at DVinfo.net

Paul Cascio · July 17th, 2009, 06:33 AM

Do I need them? Never seen them shipped seperately from a wire before.

Paul Cascio · July 18th, 2009, 07:23 AM

Okay, you guys flunk. I looked it up myself and here's what Wikipedia states:

A ferrite bead (core) is a passive electric component used to suppress high frequency noise in electronic circuits. Ferrite beads employ the mechanism of high dissipation of high frequency currents in a ferrite to build high frequency noise suppression devices. Ferrite beads may also be called ferrite cores, ferrite rings, ferrite EMI filters, a ferrite choke or mistakenly as ferrous beads.

Bob Thieda · July 18th, 2009, 08:11 AM

OK Paul...but what are we suppose to do with them?

Paul Cascio · July 18th, 2009, 08:57 AM

They are in the box with an HMC150. I guess you put them on the output wires if you need them.

Paul R Johnson · July 18th, 2009, 09:32 AM

Some countries have very stringent regulations on noise emmisions, like the UK - the problem with modern kit especially kit with switch mode power supplies is that they generate lots of 'interference' style noise, which often gets carried by the cabling into other pieces of kit. On top of this, most stuff nowadays have plastic cases. Some, like laptops, have an internal lightweight metal screen, but some don't bother. If you live near something with high output radio frequencies in use (I live next to a fire station), then the interconnecting cables can act as a sort of antenna, allowing the Radio Frequency energy into your system. I suffered from this in my edit suit, with the fire calls being heard at low level through the monitors. These ferrite filters, which simply have a loop of your cable passed through them allow low frequencies to pass through unaffected, but any higher frequency energy gets blocked by the filter. In my case, nearly, but not quite curing my problem. I've found them pretty useful on the power supply to my Dell laptop when I use it to feed a PA system. There is a large amount of background noise when the latop runs on mains power, but adding a ferrite ring removes most of this. If you have a bigger problem, then the magnet inside an old loudspeaker works pretty well too - just pass the cable through it half a dozen times, and then tape it up.

Larry Hill · July 23rd, 2009, 09:25 PM

Quote:

Originally Posted by Bob Thieda

OK Paul...but what are we suppose to do with them?

The 150 manual has pretty complete instructions on how to use these on page 72-73.

Bob Thieda · July 24th, 2009, 08:48 AM

Quote:

Originally Posted by Larry Hill

The 150 manual has pretty complete instructions on how to use these on page 72-73.

The manual, Larry? Like I use the manual....LOL...

Seriously, thanks...doesn't look like I need them, then.
I haven't found a need to hook up the camera to anything with a cable...

Bob T.

July 17th, 2009, 06:33 AM	#1
Paul Cascio Trustee Join Date: Sep 2004 Location: Bristol, CT (Home of EPSN) Posts: 1,192	HMC150: What do the Ferrite Cores do? Do I need them? Never seen them shipped seperately from a wire before. __________________ Paul Cascio www.pictureframingschool.com

July 18th, 2009, 07:23 AM	#2
Paul Cascio Trustee Join Date: Sep 2004 Location: Bristol, CT (Home of EPSN) Posts: 1,192	Okay, you guys flunk. I looked it up myself and here's what Wikipedia states: A ferrite bead (core) is a passive electric component used to suppress high frequency noise in electronic circuits. Ferrite beads employ the mechanism of high dissipation of high frequency currents in a ferrite to build high frequency noise suppression devices. Ferrite beads may also be called ferrite cores, ferrite rings, ferrite EMI filters, a ferrite choke or mistakenly as ferrous beads. __________________ Paul Cascio www.pictureframingschool.com

July 18th, 2009, 08:11 AM	#3
Bob Thieda Major Player Join Date: Jan 2006 Location: Carol Stream, IL Posts: 541	OK Paul...but what are we suppose to do with them? __________________ Bob T.

July 18th, 2009, 08:57 AM	#4
Paul Cascio Trustee Join Date: Sep 2004 Location: Bristol, CT (Home of EPSN) Posts: 1,192	They are in the box with an HMC150. I guess you put them on the output wires if you need them. __________________ Paul Cascio www.pictureframingschool.com

July 18th, 2009, 09:32 AM	#5
Paul R Johnson Inner Circle Join Date: Nov 2005 Location: Lowestoft - UK Posts: 4,045	Some countries have very stringent regulations on noise emmisions, like the UK - the problem with modern kit especially kit with switch mode power supplies is that they generate lots of 'interference' style noise, which often gets carried by the cabling into other pieces of kit. On top of this, most stuff nowadays have plastic cases. Some, like laptops, have an internal lightweight metal screen, but some don't bother. If you live near something with high output radio frequencies in use (I live next to a fire station), then the interconnecting cables can act as a sort of antenna, allowing the Radio Frequency energy into your system. I suffered from this in my edit suit, with the fire calls being heard at low level through the monitors. These ferrite filters, which simply have a loop of your cable passed through them allow low frequencies to pass through unaffected, but any higher frequency energy gets blocked by the filter. In my case, nearly, but not quite curing my problem. I've found them pretty useful on the power supply to my Dell laptop when I use it to feed a PA system. There is a large amount of background noise when the latop runs on mains power, but adding a ferrite ring removes most of this. If you have a bigger problem, then the magnet inside an old loudspeaker works pretty well too - just pass the cable through it half a dozen times, and then tape it up.