TinyPFA is firmware from Erik Kaashoek for NanoVNA-H4 hardware for accurate measurement of oscillator and clock source stability.
I was so impressed with the possibilities of the project, I purchased a new Nanovna-H4 v4.3 a couple of weeks ago to dedicate to this application.
Anticipation got the better of me, and I put tinyPFA onto my existing Nanovna-H4 v4.3 to evaluate it, and was not disappointed.
Anyway, the recently ordered device arrived.
Above, the new tinyPFA at work.
Commissioning the new hardware involved these steps:
- test it on the supplied firmare, inspect an uncalibrated sweep on a 50 ohm termination, calibrate it 1-101MHz and inspect some sample sweeps.
- uncase the thing, inspect the PCB for defects, remove the shields and carefully check the soldering of the SMA connectors;
- fix the SD slot: NanoVNA-H4 v4.3 – improving the SD card slot;
- fit SMA connector savers, 20dB SMA pads, BNC(F)-SMA(M) adapters;
- calibrate Vbat and label the case;
- replace the case screws with M2x12 304 socket head self tapping screws;
- load current tinPFA firmware and test.