Looking at the thread about noise cancelling I remembered a post by LLoyd Butler vk5br see http://users.tpg.com.au/users/ldbutler/LFNoiseCancel.htm We had a discussion of this about a year ago. Paul Daulton K5WMS beacon WMS 187.492 khz qrss30/slow 24/7 Jacksonville,Ar 72076 em34wu