2014-05-24 I was able to buy a real Garmin GPS 18 L ... 6 years ago
I was able to buy a real Garmin GPS 18 LVC secondhand. It's now on the roof of our shed. The first thing I want to do is repeat my plotting of GPS satellite positions from $GPGSV messages and plotting of GPS satellite positions and signal strengths from $GPGSV messages measurements with data from this unit. After that has run for a while I'll configure ntpd to get the correct time from the GPS unit and the PPS signal. And again, the resulting plot of gps satellite positions versus signal strength is not very helpful in finding out which part of the sky is obscured.