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Old May 20th 04, 10:29 PM
J M Noeding
 
Posts: n/a
Default DC saturation for ferrite cores

Hi
have noted the following measurement (from LA7MI) forAmidon
FB43-4301, and wonder if someone knows more available data for actual
ferrite- and iron-powder cores to be used in transmitters?

For a Amidon FB43-4301 the inductance drops by 50% for 1.2At. 3At for
75% reduction. One should keep the DC-current below the value of 0.5A
to keep the reduction below 0.5. In the example above this rule is
used, but the best is to use push-pull arrangement and the DC
magnitation is kept to a minimum level. The inductance reduction is
stored and the effect is called remanence, cores used for direct
current should have air-gap

Will write a page - http://www.noding.com/pictures/la8ak/n12.htm for
constructing RF power amplifier based on an article written by LA7MI
and distributed to a local London radio club in 1992

73
Jan-Martin
LA8AK
http://home.online.no/~la8ak/c.htm