Number of satellites visible
	RasPi-3, U-blox 6M, downstairs 25 mm patch, south-facing corner Potentially visible Actually used
	RasPi-8, u-blox MAX-M8Q, upstairs Patch antenna, south-facing window Potentially visible Actually used
	RasPi-9, u-blox MAX-M8Q, upstairs Patch antenna, south-facing window Potentially visible Actually used
	RasPi-10, u-blox MAX-M8Q, upstairs Mag mount patch antenna, room interior Potentially visible Actually used
	RasPi-11, u-blox MAX-M7Q, upstairs Patch antenna, south-facing window Potentially visible Actually used
	RasPi-12, u-blox MAX-M8Q, upstairs Patch antenna, south-facing window Potentially visible Actually used
	RasPi-13, u-blox MAX-M8Q, upstairs Patch antenna, unheated cupboard, north wall Potentially visible Actually used
	RasPi-15, u-blox MAX-M8Q, upstairs Patch antenna, interior, south-facing room Potentially visible Actually used
Average SNR
	RasPi-3, U-blox 6M, downstairs 25 mm patch, south-facing corner GPS SNR average
	RasPi-8, u-blox MAX-M8Q, upstairs Patch antenna, south-facing window GPS SNR average
	RasPi-9, u-blox MAX-M8Q, upstairs Patch antenna, south-facing window GPS SNR average
	RasPi-10, u-blox MAX-M8Q, upstairs Mag mount patch antenna, room interior GPS SNR average
	RasPi-11, u-blox MAX-M7Q, upstairs Patch antenna, south-facing window GPS SNR average
	RasPi-12, u-blox MAX-M8Q, upstairs Patch antenna, south-facing window GPS SNR average
	RasPi-13, u-blox MAX-M8Q, upstairs Patch antenna, unheated cupboard, north wall GPS SNR average
	RasPi-15, u-blox MAX-M8Q, upstairs Patch antenna, interior, south-facing room GPS SNR average
Per-PC GPS data is here, and timekeeping graphs may be seen here.

Other periods: day week month year

How were these plots generated?

Using the Raspberry Pi as a Wi-Fi Plane Plotter server
Installing and configuring the Raspberry Pi
Using the Raspberry Pi as a stratum-1 NTP server