Most Popular Articles
A Bit More on Ferrites
The discussion on ferrites and how to use them (November and December 2011 Tech Tips) seems to have hit home with many of fellow broadcasters out there. In fact, my friend Clay Freinwald from Seattle wrote me:
"I trust I am like most and have a collection of these ferrites left over from previous projects or things I have scrapped. For me, they end up in a drawer. The real issue here is what is the core material and how will it perform at AM or FM frequencies? Then again even if the material has a label (not likely) how do you know what that means? Sure it's easy to go out and buy something that's pre-packaged (and labeled), but what about the collection in the drawer in your shop?" Clay forwarded a link regarding a method of identifying the ferrite mix.
You'll need an impedance bridge (and signal generator) for that method.
Another good method I found with a little search explains how to tell using either a grid dip oscillator or a plain LCR meter. The link I originally found is no longer active, but search for the appropriate terms and you should be able to find the information.
Another useful resource regarding ferrites is this data sheet from CWS Bytemark.
And finally, by way of the Pubtech message list: Magnetics is a source of the large ferrite "donuts" that go around transmission lines.
Irwin is transmission systems supervisor for Clear Channel NYC and chief engineer of WKTU, New York. Contact him at firstname.lastname@example.org.
Acceptable Use Policy blog comments powered by Disqus
[an error occurred while processing this directive]
Today in Radio History
The history of radio broadcasting extends beyond the work of a few famous inventors.
Read each issue online in our Digital Edition Format in your Web browser.
EAS Information More on EAS
The feed provides feeds for all US states and territories.
Need a calendar for your computer desktop? Use one of ours.
Information from manufacturers and associations about industry news, products, technology and business announcements.
Browse Back Issues[an error occurred while processing this directive]
Also in the November Issue
- Trends in Technology: HD Radio Transmission Update
- Franken FM Stations
- Wi-Fi on Wheels: The Connected Car
- Field Report: Yamaha MG10XU
- Transmitter Site Cleanup