Jacob, The correct term that fits the definition of >behavior of the metal during variation of heating temperatures. is CTE or coefficient of thermal expansion. Thanks Ryan Grant Advanced Technology Engineer MCMS (208) 898-1145 [log in to unmask] > -----Original Message----- > From: <Jacob Pao King Hing> [SMTP:[log in to unmask]] > Sent: Wednesday, October 11, 2000 5:52 AM > To: [log in to unmask] > Subject: Re: [TN] Thermohidrograph > Importance: High > > Brian, > > Thanks for the fast response. > > But the definition that I get from the person who asked me is as per > below: > > Definition: Thermohydrograph is basically the its characteristics and > behavior of the metal traces within the board during exposure to variation > of heating temperatures. > > Is his definition correct?? Or is he's trying to express his understanding > as per above but used the wrong term? > > Regards, > > Jacob Pao > > > > -----Original Message----- > From: Brian Ellis [ <mailto:[log in to unmask]>] > Sent: Wednesday, October 11, 2000 5:33 PM > To: TechNet E-Mail Forum.; Pao, JacobKH > Subject: Re: [TN] Thermohidrograph > > > A thermohygrograph, which is what I assume you are meaning, is an > instrument to record the temperature and relative humidity. It usually > consists of a drum, rotating over 24 hours, on which is clipped a paper > chart, with two pens drawing squiggly lines, one attached to a bimetal > spiral for the temperature and the other to a hair hygrometer movement > for the humidity. Very useful for putting into rooms where you are > stencilling solder paste, etc. to check that the environment is > correctly controlled. > > Brian > > > "" wrote: > > > > Technetter, > > > > May I know what does the term "thermohidrograph" mean? Is it a test > > measurement for PCB? > > > > Regards, > > > > Jacob Pao > --------------------------------------------------------------------------------- TechNet Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF TECHNET 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 ---------------------------------------------------------------------------------