I just received a heads-up email from Adafruit (in the US).
They have a new uP module coming out shortly that might be good to use as the base for your own VNA/SA/O-scope/etc project:
ST takes flight in this upcoming Feather board. The new STM32F405 Feather (video) that we designed runs CircuitPython at a blistering 168MHz ¨C our fastest CircuitPython board ever! We put a STEMMA QT / Qwiic port on the end, so you can really easily plug and play I2C sensors.
This Feather has lots of goodies:
STM32F405 Cortex M4 with 1MB Flash, 168MHz speed
3.3V logic, but almost all pins are 5V compliant!
USB C power and data - our first USB C Feather!
LiPo connector and charger
SD socket on the bottom, connected to SDIO port
2 MB SPI Flash chip
Built in NeoPixel indicator
I2C, UART, GPIO, ADCs, DACs
Qwiic/STEMMA-QT connector for fast I2C connectivity
Unfortunately, no pricing yet.
