#326: How to Measure the impedance of "unknown" coax using a NanoVNA @w2aew

w2aew | #326: How to Measure the impedance of "unknown" coax using a NanoVNA @w2aew | Uploaded January 2021 | Updated October 2024, 7 hours ago.
This short tutorial video shows how to use the NanoVNA to measure the impedance of an unmarked piece of coax transmission line. It uses the unique impedance transformation that occurs with a quarter-wavelength transmission line. By measuring the resistive component of the line at a frequency at which the line is a quarter-wavelength long, the unknown line impedance is simply the square root of the product of the termination impedance and the measured value.
See this playlist of additional tutorials using the NanoVNA:
youtube.com/playlist?list=PL4ZSD4omd_AylEyNCQYR3RcEb0olukPEJ
Notes from this video can be found here:
qsl.net/w2aew/youtube/unknownCoaxZ.pdf

#385: How to quickly tune the Penntek TR-45L Z-match tuner

#296: SSB & AM RF Envelopes, Peak Envelope Power (PEP), Average Power and more

#272: Vintage Tech: Sencore TC162 Tube Tester: How to use, tips and peek inside

#360: Mini Review: The BaMaKey TP-III miniature Morse Code paddles/key by BaMaTech

#303: What is a Pulse Counting FM Demodulator | Detector | Discriminator?

#289: Back to Basics: Zener Diodes - How to Use | Applications | not all created equal

#251: Using RSA306 to capture & analyze frequency hopping signals | Bluetooth example

#349: Club Presentation: Smith Charts - the NanoVNA and your antenna - matching network design

#309: Radio Repair: Kenwood TS-940S Battery Replacement

#239: Repair of Kenwood TH-F6A radios Push to Talk switch

#237: 4 Wire Resistance Measurement | Kelvin connection