Or turn that around: how sloppy can you be with HF construction techniques and still have reasonable results?
Peter
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On Aug 7, 2019, at 8:29 PM, alan victor <avictor73@...> wrote:
Yes, that is an excellent test. If you make use of a somewhat narrow sweep so with 101 data points you can obtain the required resolution, you can find the +/- 45 degree phase shift points for S21. This will pull out the -3 dB bandwidth. I'll have to see if I can conduct such a test.
However, for now I have been conducting a much simpler measurement challenge. That is after CAL, obtaining a reasonable accurate measurement of inductors and capacitors thru the HF region, say 30 MHz max. I tend to be a bit lazy and like alligator clips, clip in the unknown and take a measurement. If you are not too sloppy you can get away with this! But I offer this up as a query...
How simple you can put together a test set for measurement of components after doing a careful cal and get reasonable results?
________________________________
From: [email protected] <[email protected]> on behalf of tuckvk3cca <tuckvk3cca@...>
Sent: Wednesday, August 7, 2019 10:49 PM
To: [email protected] <[email protected]>
Subject: Re: [nanovna-users] Measurement challenge
A good exercise is to use your VNA to measure the very high unloaded Q of Toroid coils. I have good success with J. Oppenheimer's KN5L method for toroids with Q up to 230 using a single turn sense coil throigh the toroid connected to the VNA. Above all the measurement's agreement with theoretical values for Q and phase shifts is a good check of your calibration.Accurate measurement of unloaded high Q is by no means trivial. See the link to his webpage below: from my Samsung Galaxy smartphone.
-------- Original message --------From: alan victor <avictor73@...> Date: 07/08/2019 21:45 (GMT+01:00) To: [email protected] Subject: Re: [nanovna-users] Measurement challenge I am not talking about calibration. THE CALIBRATION BY WHATEVER METHOD YOU DESIRE IS NOW DONE. Complete. Now we desire to measure some components. We are now in a position to use the NanoVNA as a component analyzer. Go measure... Alan
