Re: How do you test a toroid -


Donald Kelly
 

I can't argue with the expense. I built my homebrew LC meter because it was only a few bucks, simple and exceeded my required accuracy.

Good luck and have fun with your project, Steve.

72 K5UOS

--- In 4sqrp@yahoogroups.com, Stephen Roberts <steverob@...> wrote:

Hi Don,

Well I can't see spending $150 for an LC meter although it would be nice to have one. I'm not really a electronic tech by any means so it's really hard to justify the expense. And from a practical point of view, building one would take me forever but it certainly looks like a worthy project. In the end, I'm sure I'll just fire it up and see what happens which is my normal method of testing ;-)

73
Steve


On Mar 26, 2013, at 9:19 PM, Donald Kelly wrote:

Hi Steve,

I assume you know the ultimate inductance of the coil you are winding. A handy tool to have is a L/C meter.
Not all toroids are alike and it is always a good idea to measure. My guess is most of the guys have one of these.

http://aade.com/lcmeter.htm

This meter evolved from a homebrew project by Bill Carver, W7AAZ. A digital readout was added later for easier use. The original project is classic in its simplicity.
It is also included in "Experimental Methods in RF Design" in the test gear chapter.

http://www.qsl.net/wm5z/cq199301b.pdf


My version is used all the time. You can see the ugly style board is very simple. The trick is in the calibration steps and having a precision calibrating capacitor.

http://forums.qrz.com/showthread.php?238952-A-Simple-Homebrew-L-and-C-Tester

Test gear is fun to build and a great way to get started in scratch projects.

Don K5UOS



From: 4sqrp@yahoogroups.com [mailto:4sqrp@yahoogroups.com] On Behalf Of w1sfr
Sent: Tuesday, March 26, 2013 11:18 AM
To: 4sqrp@yahoogroups.com
Subject: [4sqrp] How do you test a toroid?


The transforming toroids are pretty tricky to wind. Is there any way to test them to find out if you've done it correctly?

73
Steve

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