OT: RF interference

[Rory McDonald]

If a device is picking up RF (local radio station I think),
will a Ferrite core suppress this problem? where is the best
place to put the core? How does the core work (basically- I am not a
designer).
Please advise if there a better solution. The device is a Video conference
system, but I dont know if the
RF is being picked up by that or the NTSC monitor it uses.
We have used them on ISDN cables (flat silver satin) and put them on next to
where the videoconference Codec 
interfaces to the lines (the IMUX). My expertise in videoconferencing doesnt
really extend to RF.
Any advice would be appreciated.
Thanks
Rory McDonald