@joeqsmith
"If the above statements are true, I am surprised there would be any question. You know the Nano is working. You know how to properly calibrate it. You have the equipment and expertise to verify your results. I'm missing something"
And that's my real question. Either I am doing something stupid or the NanoVNA I have is broken. Your help and continued feedback are appreciated.
Here is what I did this morning:
1) Make sure NanoVNA battery is fully charged.
2) Turn on unit. Range is 144-148MHz as previously set
3) Select CAL, then RESET
4) Select CALIBRATE, then step through OPEN, SHORT, LOAD, ISOLN (2x 50ohm loads), THRU (using supplied 6" cable), then DONE. I used my R&S SMA lab standards and saved the calibration result in memory zero.
5) After Pressing DONE, with nothing attached, the display shows the SWR trace above the first horizontal division and the value for SWR is 1:2..38. The impedance is shown at 118 ohms with 3.02nH. Smith chart is stable.
6) reinstalling a 50 ohm standard, gives 49.9 ohms and 15.2 nF and a SWR of 1:1.00 SWR trace is at the bottom of the display. Smith chart is stable.
7) reinstalling a short standard gives 944miili Ohms and 4.15 nH and SWR of 1:131 (varies from 128-133) SWR trace is at the top of the display. Smith chart is stable.
a 150 ohm, non inductive 5% leaded resistor gives 81.8 ohms 4.98 nH and a SWR of 1:1.64 Smit chart is stable.
For reference, I recheched the same resistor on my 8753 and it measured an SWR of 1:3.002.
Nothing else was done to the NanoVNA and I listed every action taken, This was done on my bench with an ESD pad. The RF environment is typical, with no high power transmitters operating nearby, as shown by a spectrum analyser with a whip antenna that I left running in peak hold mode spanning 1-3200MHz while these tests were in progress. No signal greater than -60dBm, except in the 2.4GHz and 900MHz bands, which had the usual Wifi, BLE and Celluar traffic.
Any ideas?