Dan, Since no one has answered, I will try. We make RF products and microphonics (cow bell is the term used here) has been a problem. The problem was traced to the VCO. Let me know if you need more information. I am not the design engineer, so my help is limited. Tenison Stone Manufacturing Engineer Telex Communications 1930 West First Street Blue Earth, MN 56013 507-526-3205 x2164 507-526-3059 (fax) "Dan R. Johnson" <[log in to unmask]> Sent by: TechNet <[log in to unmask]> 12/05/2002 05:01 PM Please respond to "TechNet E-Mail Forum."; Please respond to "Dan R. Johnson" To: [log in to unmask] cc: Subject: [TN] A shot in the dark Maybe someone on Technet knows or knows someone who does know about microphonics as an error factor in RF circuits. I need to have an outside source for things like; -an engineering definition of microphonics as a source of "noise". -a measurement technique -an explanation of the physics of microphonics i.e. how motion is required to generate what degree of noise. Thanks, Dan --------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 -----------------------------------------------------