Measure the Characteristic Impedance (Zo) of an Unknown Coax (052)

So, you just found a roll of coax that you'd like to use, but it is unmarked. You have no idea what its characteristic impedance is. How can you measure that?

In this video I am going to show you three ways to accomplish this task. Two of these methods use something like the nanoVNA or similar device. The third method uses a time domain method which has been around for a very long time.

All three methods are quite simple and straight forward.

SPEED OF LIGHT VALUES
-----------------------
11802.85E6 inches/sec ... 11802.85 mega-inches/sec
29979.24E6 cm/sec ... 29979.24 mega-cm/sec

Time Markers for Your Convenience
----------------------------
00:05 Introductory comments
01:13 The VNA Methods
01:15 Measurement Preparations
04:27 VNA WAY #1: 1/4 Wavelength Method
06:24 VNA WAY #2: L/C Method
09:18 The TDR Method
14:54 Debriefing: Three Results Compared
15:45 Final Comments & toodle-oots
02:08 First Video in the VF series
10:21 Measuring VF: TDR Method Video
-----------------------------