thought i was going crazy so bought another RTC (got a ds3231) this time. Followed the instructions and hey presto!!! Still not working
I flashed another SD card with Raspian and the RTC works perfectly there. So i know the hardware is fine.
There seems to be something somewhere that is forcing the date and time back to Fri Feb 12, 02:28:16 (year 2006). I have looked and looked but cannot find anything anywhere.
Going to GPS isn't an option as it won't give me anything other than a further power drain when i'm out in the field and i'll still have to set my mount manually initially anyway.