>> Hello everyone, I am looking for a manufacturer of an active "comb filter" to notch out 50Hz+harmonics noise from bio-medical signals. Can anyone help. Regards Shaike Raz <<
I encountered a similar problem almost 20 years ago and thought about using a digital delay line to generate a powerline period delayed signal and combining it with the original. In the end, and for our test lab, I could not justify the cost and effort to build this. Have you considered injecting a small amount of the 50 Hz noise antiphase into the signal chain? In vacuum tube days this was known as a "hum-bucker." Cortland This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: emc_p...@symbol.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc