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Karl Jan, My SAA-2N measures about -12dBm at 8MHz CW, but the signal pulses on and off during the sweep. (It is -12dBm during the on times, measured with an HP8563E SA.) I am using the Ojisan version

For swr plot you can use the value of 6:1 each side of center freq. Find those 2 values of freq, find their difference and divide into the center freq to get operating Q. If you double that value,

"the logmag is extremely narrow and touchy to be resonant" Yes, that one. And you should be seeing a pretty decent return loss value.

You will be measuring S11, a one port measurement. Set the display for log magnitude dB. So the sweep should show an excellent return loss at the desired frequency set for the PI MATCH, say 7.1 MHz

That’s a good way to put it Roland. Thanks for the link. -- VE6WGM

Did you calibrate on saver and not just on the NanoVNA?

Simultaneous is probably overkill — particularly because non-linearities would break it — but yes, a single receiver at each port would make sense. There's no shame in mixing, so long as the

Questions I've not even begun to think about... (although, yes, directional arrays are things that I expect to want to do at low UHF within the next 12 months). - Roland 9V1RT

Hi Alan, OK I have been using for traces. a smith chart, and a swr line, and a log mag, Smith is well a smith, the SWR seems broad, where the logmag is extremely narrow and touchy to be resonant with

I'd suggest that although use of the NanoVNA should not be limited to those with engineering degrees, it would be helpful for most beginners to at least understand what the S11 and S21 parameters

I should add, this takes the pi net as a single tuned resonator, that the match at fo is good,say 20 dB return loss and for a lossless network, S11^2+S21^2=1. See how to get Q from a single tuned

Hi Joe, The Q you will measure is the operating Q and that probably is the one you want. That is to say, we have the Q on the plate side of the tube and the Q on the antenna side... that is the 50 ohm

I have a NanoVNA-H4, Using it, It it possible to be able to measure the "Q" of a Pi output network of a HF frequency Amplifier? I can measure the match it is making for between the tubes and the

Jim, You are doing some interesting experiments. Explained very well and helped me understand the issues. I look forward to seeing how you progress. Thanks - Roger

Very good. Thanks.

It is easy to come to the conclusion that the S11 phase angle as seen on the nanoVNA (CH0 PHASE 90..) is the relationship in a device under test between the voltage and current in that device, and I

I'm still struggling with my faulty nanoVNA SAA-2N :-( In addition to the SAA-2N I have got a nanoVNA-F, a nanoVNA-H4 and a small "very tiny...". The other units are working ok, but I really want to

Sure, I think so. The bare NanoVNA has about 80 dB dynamic range.? If you lose 10-15 dB due to dividers, etc. then you're at 60 dB. It would be interesting to compare the "resistive divider" vs

Hi Jim, Do you think there is adequate dynamic range in this 2 vna system to measure a run of the mill device, like a 2N3904? At HF the s21 might be 20 dB while the s12 is -40 dB. Regards, Alan

On 10/14/21 6:03 AM, Roland Turner via groups.io wrote: > On 14/10/21 8:14 pm, Joe Smith via groups.io wrote: > >> Some background my be found at these two links: >> >>