Mobile GPS logging Geiger Counter Project Pt.2

Archived from radmon.org - originally posted 19/03/2016

I have sorted the battery issue by adding a couple of 18650 Lipo's and a buck converter to regulate the voltage to 5.0V. That seems to be holding up well. The entire unit (logger and counter) consume about 10ma at 20CPM background radiation so roughly working out if my batteries are 2000mAh (they state 2600mAh but I doubt I will get that) and the unit uses 10mA then it should last for around 200 hours! I just need to sort a charging circuit now to charge the batteries when the unit is powered from 12v from the car, or mains adapter.

I went out for a quick test with it and it seems to be OK except for sketchy GPS data. I think I need to improve the GPS antenna, so adding an external antenna should sort that. I have a Peugeot car with heat reflective windscreen and it plays havok with most cheaper GPS receivers. At least I'm hoping that is the issue!

Here is the data for anyone interested and a quick picture of what it looks like so far: https://www.google.com/maps/d/viewer?mid=zasLAdbQXqtw.kxVyakPPw-s0