Towertalk
[Top] [All Lists]

Re: [TowerTalk] Ferrite material Laird 28

To: towertalk reflector <towertalk@contesting.com>
Subject: Re: [TowerTalk] Ferrite material Laird 28
From: Jim Brown <jim@audiosystemsgroup.com>
Reply-to: jim@audiosystemsgroup.com
Date: Mon, 27 Mar 2017 16:36:47 -0700
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
On Mon,3/27/2017 2:12 PM, Richard (Rick) Karlquist wrote:
What I meant by loosier is that in a common mode
choke, there would be more heat dissipation loss
with the Laird.  I did NOT mean that the series
resistance was higher.

Not necessarily. Remember that power is I squared R, and if R is sufficiently large, I falls to the point that power is small (because it's falling twice as fast as R increases). OTOH, that R is undesired when using the core in a real transformer (that is, the core carries all of the flux for the differential power). I know you know this, Rick, but this is for others on the reflector who may not.

73, Jim K9YC

I agree Fair-Rite's web site is by far the best
in the industry.

73
Rick N6RK

On 3/27/2017 12:07 PM, Jim Brown wrote:
On Mon,3/27/2017 4:46 AM, Richard (Rick) Karlquist wrote:
I have measured various competitor's
"equivalents" to material 43 and the found
that they are considerably lossier.

For common mode chokes, lossier is better. But so is the shape of the
curve of loss vs. frequency, and so is resonant frequency. You either
need to wind chokes and measure them or have graphs of mu' and mu'' vs
frequency to compare with the Fair-Rite materials. Laird's website
appears to be totally inscrutable with any of this, FAR, FAR, FAR behind
Fair-Rite's. Laird's seems to have been done by a data guy, Fair-Rite's
by an applications engineer who actually understands what's needed to
choose a part and design using it.

73, Jim K9YC

_______________________________________________



_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk




_______________________________________________



_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk

<Prev in Thread] Current Thread [Next in Thread>