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Consider the case of a 100 foot long, 50 ohm coax feedline on 20 meters. And let's look at three different types of coax. Below are the losses for 100 feet with a VSWR of 1:1 RG58 - 1.55 dB RG8X -

Other than the 2:1 reading on the SWR meter what negative effect have you experienced. 55 years worth of rigs, tube and solid state, I have never experienced an ill effect from a 2:1. Warren Allgyer

some rigs are not that happy with 1:2 SWR dg9bfc sigi Am 12.11.2024 16:10 schrieb "Warren Allgyer via groups.io" <allgyer@...>:

You have a resonant antenna with an SWR of 2:1 which is completely inconsequential at 40 and 20 meters. There is no functional reason to do anything to correct this; you will see no improvement in

A basic PC sound interface is simply a group of analog-digital and digital-analog converters. They operate at least in 16 bit resolution, while many have 24 bits. The sample rate is settable, at least

Hi Steve Thank you Steve, helpful link. 73's Nizar

You might consult the docs for a start. From the beginners guide: https://nanovna.com/?page_id=46 look at number 4 Steve N5TIN

It seems you might look at the scale settings items

I believe it’s a summary of operating modes/settings for diagnostic use

Hi All What does mean the "DRSTX" on the left side of screen ? 73's Nizar

For measurements in the audio-frequency range, you might want to look at the Scimpy software package. It was designed as a means of using a PC sound card, and a simple resistive divider network, to

There have been a couple of audio VNA's (AVNA) in QEX. Here is mine: http://www.janbob.com/electron/AVNA1/AVNA1.htm This is not a commercial product, but rather a construction project with a PCB,

There was an article in Jan/Feb 2024 QEX describing using a spectrum analyzer with tracking generator and two mixers, which is essentially the scheme I described above. They used a 30 to 31MHz sweep

Only if the PC sound card provides phase information. I do not know whether or not they do. 73, Don N2VGU

I have seen articles describing ham use of, and there are commercial versions of, UPconverter/DOWNconverter products for using low(er)-frequency VNAs to measure higher-frequency and even waveguide

an oscilloscope would be a much better option. Particularly those that have the audio range. Otherwise, could divider circuits, say a 10 or 20 to 1 ratio be used to measure audio frequencies?

Since the NanoVNA covers from 10kHz up, one can use the sound system of a PC with suitable software to provide the lower frequency coverage. Even the most basic sound chip in a PC will cover 20Hz to

ODD half-wavelengths of ANY impedance transmission line will repeat the impedance presented at the far end. It is not confined to RG-58 or to 50Ω line. 73, Don N2VGU

It's not quite what you want but the old HP 4800A Vector Impedance Meter does 5 Hz to 550 kHz. Manual (as in 'hand operated') sweeping though! DaveB, NZ

Neil, The HP3577A VNA with HP35676A test set covers from 5Hz to 200MHz. Only weighs about 70lb. Some versions of the NanoVNA-H4 firmware work down to 800Hz (I don't know how well). I don't know if