Hello Padma, When doing the differential (4port) calibration what type of through calibration are you doing.. unknown or defined and are you using all 6 through paths for the calibration? Best Regards, Heidi -----Original Message----- From: si-list-bounce@xxxxxxxxxxxxx [mailto:si-list-bounce@xxxxxxxxxxxxx] On Behalf Of padma gundala Sent: Thursday, September 11, 2008 7:17 AM To: Richard Jungert Cc: si-list@xxxxxxxxxxxxx Subject: [SI-LIST] Re: Calibration using VNA > To: "Richard Jungert" <r_jungert@xxxxxxxxxxx> > Date: Thursday, September 11, 2008, 7:09 AM > Hi Richard & others, > > I have attached the screen shot ,(photo).jpeg for the load > calibration. > However, even, at thru calibtaion the curve of the loss > looks choped heavily,of course the line straighter closer to 0db and > when I look at the smith chart format, the circle must > spiral with smooth lines to show attenuation. however it > looks again a messy spiral. > > So do you think I have made some mistake in my settings for > the VNA? > > Thanks, > > Padma --- On Mon, 9/8/08, Richard Jungert <r_jungert@xxxxxxxxxxx> wrote: > From: Richard Jungert <r_jungert@xxxxxxxxxxx> > Subject: RE: [SI-LIST] Calibration using VNA > To: "padma gundala" <pgundala2001@xxxxxxxxx>, si-list-request@xxxxxxxxxxxxx > Date: Monday, September 8, 2008, 2:31 PM > Peter. > > Can you take a picture and send me the picture of what that > looks like on the VNA screen? Send the Picture file and I > will try to diagnose it. > > Richard Jungert > > > Date: Mon, 8 Sep 2008 14:26:10 -0700 > > From: pgundala2001@xxxxxxxxx > > Subject: [SI-LIST] Calibration using VNA > > To: si-list@xxxxxxxxxxxxx > > > > Hi, > > > > I'm doing a differential insertion loss > calibration using a VNA. > > I get the expected loss line curve for open and short. > > However for load , the loss curve is not smooth, it is > chopped throughout. > > Can anyone tell what could be the reason. The 50ohm > load and thru loads are from the CAL KIT. > > > > Appreciate any thoughts ! > > > > Thanks, > > > > Peter > > > > > > > > > > > ------------------------------------------------------------------ > > To unsubscribe from si-list: > > si-list-request@xxxxxxxxxxxxx with > 'unsubscribe' in the Subject field > > > > or to administer your membership from a web page, go > to: > > //www.freelists.org/webpage/si-list > > > > For help: > > si-list-request@xxxxxxxxxxxxx with 'help' in > the Subject field > > > > > > List technical documents are available at: > > http://www.si-list.net > > > > List archives are viewable at: > > //www.freelists.org/archives/si-list > > or at our remote archives: > > http://groups.yahoo.com/group/si-list/messages > > Old (prior to June 6, 2001) list archives are viewable > at: > > http://www.qsl.net/wb6tpu > > > > > > _________________________________________________________________ > See how Windows Mobile brings your life together-at home, > work, or on the go. > http://clk.atdmt.com/MRT/go/msnnkwxp1020093182mrt/direct/01/ ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List technical documents are available at: http://www.si-list.net List archives are viewable at: //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List technical documents are available at: http://www.si-list.net List archives are viewable at: //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu