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David, Good stuff, thanks for posting. Assuming the connectors physically stout enough to give repeatable results, would it be possible to calibrate out most of the errors encountered in a cheap or

With the recent discussion about high return loss loads, I made the point that it is a bit pointless worrying about it unless there’s firmware support for calibration kits in NanoVNA, which as far

I shall contribute another nit: it's not 377 ohms, 376.730... ohms (approximately 120*pi, but I think that's a coincidence) - and yes it's the ratio of E field (V/m) to H field (A/m) in a vacuum "far"

Interesting concept. Why does the impedance of the Universe change with distance??? If think you are confusing 'Far Field' with impedance.????? Kent Just to clarify.? 377 ohms is? a physical

Perhaps you bought the wrong Harbor Freight DMM. I compared my free-with-purchase HF 69096 against my very expensive $10 UT10A. The UT10A shows 0.0 ohms with the probes touching almost immediately.

These can of worms taste better with HOT Sauce and you get what you pay for !

Just to clarify. 377 ohms is a physical constant relating the magnitudes of the electric and magnetic fields of electromagnetic radiation travelling through Free Space. This only occurs when you are a

This is only true if the current on the transmission line has the same magnitude (but opposite directions) on the two conductors. If not the transmission line will radiate. Take the case of a dipole

Peter, I have attached a measurement of port 2 return loss from my NanoVNA V2, bought from tindie. This one seems to be meet the specs (-20.3dB @1.5GHz and -15.5dB @3GHz). There is also significant

Only on the input, the output is always 377 Ohm. Example would be Yagi's with 50 or 75 ohm inputs. Now, how well you match the 50/75 input to the 377 outputis determining Gain and SWR.??? Kent

yeah, I'd just go hunting through the Minicircuits or Johansen catalogs and look for something that does the function - I have no idea how they make them internally (well, I know it's some windings on

Hmmmm, I have a question. The test/ education board available for about ?15 has simple loads, capacitors attenuators, etc with leads which have those inferal minute connectors to select which circuit

For a 2:1 impedance transformer, 14:10 turns ratio gives 1.96:1 impedance ratio which may be close enough, or 17:12 turns ratio gives 2.007:1 impedance ratio (<0.35% error). A few minutes playing

I have N, SMA, and OSM series precision cal. kits from HP. I made a DC measurement of the 50-ohm standard loads for these three connector series from these kits using the following instruments (what I

So - the Right-Hand-Rule applies to antennas as well....?

There's a couple ways to approa

Yes, I used to know that. But having radiation described as the result of an accelerating charge got me thinking about it in a new way. I guess that creates a magnetic field around the dipole wires,

So you are saying a Yagi is a transformer with multiple taps? :)

The intention of the following: 1) ALL TRANSMISSION LINE(s): Fields close onto themselves. The system is self contained as far as the fields are concerned. 2) ANTENNA(s): Fields open onto space

Thank you for this clarification. Great Job! I love the device! Wolfgang ------------------------------------------------------------ RFC1925: (3) With sufficient thrust, pigs fly just fine. However,