On 23/04/2013 20:52, Bruce wrote:
You may well be right, but I did pick up some source code to do it a few years ago. Excuse me for being cheeky, but is that recorder you mentioned an expensive bit of kit and does it have some kind of data logger?

The sunshine recorder was around £200 and yes I've attached a datalogger
(can't remember how much that was but it is an ADC-16 from Pico Technology).

The recorder actually gives a voltage (1.3V) when the sun is shining and
0.1V when the sun is not shining. This is a continuous output and from
that you can work out the total sunshine for the day.

--
Nick G
Otter Valley, Devon
20 m amsl
http://www.ottervalley.co.uk