Re: Torroid cores

 * Carbons Sent to: usa-tesla-at-usa-dot-net

 > Hey Folks, Despite carefully looking through the many          
 > electronics catalogs that I get, I still haven't found a       
 > source for torroid cores for filter inductors. Where _do_ you  
 > get them?

Get the latest catalog from Marlin P. Jones & Assoc. Inc.
P.O.BOX 12685, Lake Park, FL  33403  USA
 Fax 1-800-4329-9937, Fax 407-844-8764, Tel: 407-848-8236
Sources for surplus: ferrite toriod cores for HV RF chokes,
Current transformers for panel ammeters, EMI line filters,
meters, power control relays, etc..

I generally find surplus ferrite core toroid chokes that are
already wound, but you will also come across bare cores. I
purchase the heaviest ones I can get, strip the old wire off
of the cores, wrap the cores with a few layers of plastic
friction tape for a little insulation, and rewind with thin
plastic insulated stranded wire. The bigger cores work better
because they give you the required inductance without having to
crowd turns of wire on the core. Cores that are too small and
then tightly wound can short out. Better to get a core that is 2
- 3 inches in overall diameter. They will have these, even if
they are not listed in the catalog, if you call and ask.

BTW, I have been advocating these type chokes, wound just this
way, for years. I had done a series of very simple experiments
that measured the relative effectiveness of these ferrite toroid
core chokes compared to various air wound chokes that coilers
have been using for years. It is interesting to note that in the
last issue of the TCBA NEWS someone came along and reported an
experiment which resulted in quantitative data which perfectly
matches my cheesy relative data of several years back.

Richard Quick

... If all else fails... Throw another megavolt across it!
___ Blue Wave/QWK v2.12