HF Loop Antenna Testing with NanoVNA


Recently I discovered the NanoVNA vector network analyzer. I had seen articles in QST magazine over the last several years and was intrigued (Ref.1/2). My first experiment was with my HF vertical antenna. I calibrated the unit for the HF band from 1MHz – 30MHz and tested the SWR (Ref.3). Next I tested my VHF Marine antenna over 150MHz – 180MHz (Ref.4). In this post I test my HF Loop Antenna over 1MHz – 30MHz. The results will be captured with NanoVNA software that interfaces with my laptop.

Initial Setup

Fig.1 NanoVNA with Open/Short/50ohm sma Terminations

Figure 1 shows the NanoVNA Port 1 connected to the HF Loop antenna RG-58 coaxial cable through a PL259/sma adapter. The first step is to calibrate the unit over the frequency range of interest. You can work directly with the unit, or use the pc software to access the unit which I did (see YouTube video). I entered the frequency range of interest which is 1MHz – 30MHz. Then I placed an Open on Port 1, followed by a Short, and finally a 50 termination.

Test Results

Fig.2 SWR of HF Loop Antenna + 4m RG-58 Tx Line at 7MHz
Fig.3 SWR of HF Loop Antenna + 4m RG-58u at 12.5MHz

Figure 2 shows the SWR of the HF Loop antenna plus transmission line tuned to 7MHz. Figure 3 shows SWR at 12.5MHz.

Fig.4 YouTube Video HF Loop Antenna Testing with NanoVNA
YouTube Channel
YouTube Channel


#1. – “NanoVNA V2 Plus4 50KHz – 4GHz Two-port Vector Network Analyzer”, P.Salas AD5X, QST Magazine April 2022

#2. – “NanoVNA Vector Network Analyzer”, P.Salas AD5X, QST Magazine May 2020

#3. – “HF Antenna Testing with NanoVNA”

#4. – “VHF Marine Antenna Testing with NanoVNA”

By Jeremy Clark

Jeremy Clark is a Senior Telecommunications Engineer and Advanced Amateur Radio Operator VE3PKC. He is the author of E-Books on Telecommunications, Navigation & Electronics.