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Old January 25th 10, 06:09 AM posted to rec.radio.shortwave
Kevin Alfred Strom Kevin Alfred Strom is offline
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First recorded activity by RadioBanter: May 2009
Posts: 544
Default Question about matching transformer (9:1 un-un)

bpnjensen wrote:
[...]
Another question on this subject - what core should be used for this
application?

Amidon, among others, has cores of many materials including 43 and 77,
both of which seem to get use in these applications; however, for RFI
problems below 10 MHz, Amidon recommends cores of J material, and my
RFI problems (while not confined to under 10 MHz) are primarily below
that frequency. Would use of J material be wise here, or for this
matching transformer would I be better using the old standbys 43 or
77, and then making lots of separate chokes from other materials such
as J?




The latter course seems best to me, since the ideal core
characteristics are likely different for the two purposes.



Again, my sincere thanks for the advice...

Bruce Jensen




You're welcome; have fun with the DX-160.


With all good wishes,




Kevin, WB4AIO.
--
http://kevinalfredstrom.com/