wrote in message
...
Two or three weeks ago I saw a UK website about some new little ferrite
cores that are intended for use on cellphone earphones.They clip on the
cellphone earphone cords/wires.Suppose to help drain off cellphone
microwave energy.They might be handy for shortwave radios too.
cuhulin

The same cores that work at 800, 1.9GHz, 2.4 GHz will likely not be useful
at HF.
The whole idea that reducing RF on the earphone will be beneficial is
nonsense.
Right along the lines with the PC card antenna that fits under the cell
phone battery.
Dale W4OP