Camcorder DC power cord core filter - woo or science?

catbasket · 5th February 2008, 04:00 AM

My JVC camcorder was supplied with a Core Filter - a 3cm long plastic gizmo with metal inserts - around which you loop the AC power adapter's DC cord to "reduce interference". The grand total of info about the core filter in the manual is -

Quote:

Attach the core filter to the AC adapter's DC cord. The core filter reduces interference. [plus diagrams showing how to fit the core filter to the DC cord]

I've used the AC adapter to charge the battery pack and also power the camera while transferring files to PC, without connecting the core filter to the DC cord, with no problems whatsoever.

Is the core filter woo or real science? If science - what does it do, how does it work and why is it a seperate gizmo clipped onto the DC cord rather than part of the power adapter?

Freethinker · 5th February 2008, 04:22 AM

It's probably a ferrite device that will filter out high frequency noise on the line that can be created by electrically noisy devices like fluorescent lighting.

technoextreme · 5th February 2008, 05:26 AM

Originally Posted by Snow

My JVC camcorder was supplied with a Core Filter - a 3cm long plastic gizmo with metal inserts - around which you loop the AC power adapter's DC cord to "reduce interference". The grand total of info about the core filter in the manual is -

I've used the AC adapter to charge the battery pack and also power the camera while transferring files to PC, without connecting the core filter to the DC cord, with no problems whatsoever.

Is the core filter woo or real science? If science - what does it do, how does it work and why is it a seperate gizmo clipped onto the DC cord rather than part of the power adapter?

It's not woo. It's just something you don't usually deal with on a daily basis. Check your computer. 1000% certainty that your computer has the same device. It's the big giant bump in the cable.

marting · 5th February 2008, 06:32 PM

Originally Posted by Snow

My JVC camcorder was supplied with a Core Filter - a 3cm long plastic gizmo with metal inserts - around which you loop the AC power adapter's DC cord to "reduce interference".

I've used the AC adapter to charge the battery pack and also power the camera while transferring files to PC, without connecting the core filter to the DC cord, with no problems whatsoever.

Is the core filter woo or real science? If science - what does it do, how does it work and why is it a seperate gizmo clipped onto the DC cord rather than part of the power adapter?

Manufacturers add these devices to reduce high freq common mode RF emissions for regulatory reasons. A device that otherwise radiates slightly more RF than is allowed will often meet specs with these. It has no effect on the operation since it doesn't alter differential signals within the wire cable.

5th February 2008, 04:00 AM	#1
catbasket atheist godfather Join Date: Jan 2002 Location: The naughty step Posts: 1,486	Camcorder DC power cord core filter - woo or science? My JVC camcorder was supplied with a Core Filter - a 3cm long plastic gizmo with metal inserts - around which you loop the AC power adapter's DC cord to "reduce interference". The grand total of info about the core filter in the manual is - Quote: Attach the core filter to the AC adapter's DC cord. The core filter reduces interference. [plus diagrams showing how to fit the core filter to the DC cord] I've used the AC adapter to charge the battery pack and also power the camera while transferring files to PC, without connecting the core filter to the DC cord, with no problems whatsoever. Is the core filter woo or real science? If science - what does it do, how does it work and why is it a seperate gizmo clipped onto the DC cord rather than part of the power adapter?

5th February 2008, 04:22 AM	#2
Freethinker Graduate Poster Join Date: Oct 2005 Location: The Uncanny Valley Posts: 1,358	It's probably a ferrite device that will filter out high frequency noise on the line that can be created by electrically noisy devices like fluorescent lighting.
	__________________ "Did it indeed seem probable, as he had once overheard Dunbar ask, that the answers to the riddles of creation would be supplied by people too ignorant to understand the mechanics of rainfall? Had Almighty God, in all His infinite wisdom, really been afraid that men six thousand years ago would succeed in building a tower to heaven?" Thoughts of the Chaplain in Heller's Catch-22

5th February 2008, 06:32 PM	#4
marting Muse Join Date: Sep 2003 Location: Rancho Santa Fe Posts: 734	Originally Posted by Snow My JVC camcorder was supplied with a Core Filter - a 3cm long plastic gizmo with metal inserts - around which you loop the AC power adapter's DC cord to "reduce interference". I've used the AC adapter to charge the battery pack and also power the camera while transferring files to PC, without connecting the core filter to the DC cord, with no problems whatsoever. Is the core filter woo or real science? If science - what does it do, how does it work and why is it a seperate gizmo clipped onto the DC cord rather than part of the power adapter? Manufacturers add these devices to reduce high freq common mode RF emissions for regulatory reasons. A device that otherwise radiates slightly more RF than is allowed will often meet specs with these. It has no effect on the operation since it doesn't alter differential signals within the wire cable.
	__________________ Flying's easy. Walking on water, now that's cool.

5th February 2008, 05:26 AM	#3
technoextreme Illuminator Join Date: Jun 2007 Posts: 3,786	Originally Posted by Snow My JVC camcorder was supplied with a Core Filter - a 3cm long plastic gizmo with metal inserts - around which you loop the AC power adapter's DC cord to "reduce interference". The grand total of info about the core filter in the manual is - I've used the AC adapter to charge the battery pack and also power the camera while transferring files to PC, without connecting the core filter to the DC cord, with no problems whatsoever. Is the core filter woo or real science? If science - what does it do, how does it work and why is it a seperate gizmo clipped onto the DC cord rather than part of the power adapter? It's not woo. It's just something you don't usually deal with on a daily basis. Check your computer. 1000% certainty that your computer has the same device. It's the big giant bump in the cable.