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I have done some Measurements on my NanoVNA. Maybe the tolerances are higher at other NanoVNA but i am very surprised of my Results. Is there anyone out wo can confirm my work?

The Frequencies are compared with an Stabilock4040 and an R&S ZVH4 Antenna-Analzyer with Spectrum Option. The Reference came from an GPS disciplined 10MHz TCXO.

73s Holger, DF6DBF

Hello Holger,
Surprised positive, or surprised negative?
What is the reference?

73, Rudolf DL5FA

On Wed, Aug 14, 2019 at 03:37 AM, <df6dbf@...> wrote:

I have done some Measurements on my NanoVNA. Maybe the tolerances are higher
at other NanoVNA but i am very surprised of my Results. Is there anyone out wo
can confirm my work?

All frequencies are dependent on the tolerance of the fixed crystal in the unit. Errors will track with this crystal. Some "black" NanoVNAs have found errors as small as 5 Hz at 30 MHz. Some "white" NanoVNAs show a larger frequency deviation of 300 Hz at 30 MHz. My $28 ebay auction "white" Gecko unit has a frequency error of 150 Hz at 30 MHz.. My black unit is much better, around 3 Hz. .

Note too, that it is easier for most of us to just just measure frequency output with a GPS disciplined counter. No need for spectrum analyzer.

Positive Surprised, but i am not an RF-Engineer. :)
Had as comparison a Rohde & Schwarz ZVH4 and a RigExpert AA-600.

The NanoVNA specification for frequency accuracy is +- 0.5 Parts Per Million. At 30 MHz it would still be in spec if the frequency error was as high as 15 Hz. My unit measures 220 Hz low at 900 MHz which is 0.24 PPM and is well within the specification.

Warren Allgyer
WA8TOD