There has been an article in the january-issue of cq-dl.
DL5SAF had problems with his telefones connected to a DSL-router. They
ringed when he transmitted on 80/160.
He experimented with rectangular ferrite-cores R80-1500 and different
winding-techniques.
He inserted the cores in every cable except the power-supply. This
solved his problem.
He submitted screenshots which show the attenuation of the 3 different
techniques. They were:
4 or more windings in a 8-shape, -33db on 3.75Mhz
24 windings, 12 on every long 'leg' of the core, -44db on 3.7Mhz
12 windings on one leg only, best overall results up to 50Mhz,
-32db on 3.75, -35db or better up to 30Mhz.
Find his article (in German, but screenshots and pictures are
multi-language :-) ) here:
http://www.elschenbroich.com/relais/entstoerung.pdf
--
73, DM4iM
_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband
|