RonL
A follow up to my earlier response with respect to measuring the chokes using an AMI 4170. This afternoon I measured two chokes with the AIM 4170 and ploted the results on the two cores, 4 turns and two cores, 5 turns graphs to show the results compared with the measurements I made using the Vector Voltmeter and voltage divider circuit. I added the new graphs to the document [at the very end] and have uploaded it to the web site. You can see from the graphs that, when I measure the chokes I have fabricated, the impedance magnitude results are lower when using the AIM 4170. 73, Tod, K0TO _____ From: Douglas, Ron [mailto:ron.doug...@sumcousa.com] Sent: Monday, August 29, 2011 11:24 AM To: t...@k0to.us Subject: Testing chokes with 31 material Todd I use an AIM-4170 VNA purchase through Array Solutions to do testing as you have described. A few things I have noticed is your table, it looks like a folding type, if it is, I have the same. One thing I have found is the metal support under the table will change the Z-Mag or impedance of the choke being tested if placed over the top of the support. Bob at Balun Design has many of the 4170 VNA plots on his website, he has helped us design our own choke for mobiles and our home antenna package. Please look at his site, he builds a very nice product. I have enjoyed reading all of your data and have a few things I would like to talk to you about if you have the time. Please use the scorpionanten...@cox.net for any and all replies. This e-mail is my real job e-mail address. I am off this wed through sat if I could give you call one of these days. Best Regards Ron Douglass NI7J scorpionantennas.com scorpionanten...@cox.net cell 623.326.8780 _______________________________________________ UR RST IS ... ... ..9 QSB QSB - hw? BK