Battery run competition, category 41

[MeindertKuipers]

The setup stopped this afternoon. Total run time 66 hrs (plus or minus 2 minutes), on 2* 1000 mAH AAA batteries, see picture.
This was a bare HP41CX with only the PPC ROM plugged, running a small user program generating primes with the NP routine.
Boost converter used is one from Polulu https://www.pololu.com/product/2560, set at an output voltage of 5.2V.
It started at prime 409 (needed some time to start the sequence), last prime seen was 74357.
I have a timelapse movie to prove, need to edit it a bit!

Regards,