I have been working¬†5 km south of Mallaig again today and I was looking forward to seeing what the RINEX data download presented this time. Alarmingly there is no data available for Mallaig so I wonder if the recent appearance of the Arisaig station is there as a permanent replacement for it. The position read in from the RINEX file and used by Trimble business centre is the same as last month and ¬†remains about 460 mm out in easting, 940 mm in northing and 240 mm for level. There are no posts on the OS web site to hint at what may be happening and I haven’t heard anything back from my email enquiry when I first stumbled upon this issue.

Thankfully my own base station occupation time was of sufficient length to get a good solution from much longer vectors; Oban, Fort Augustus and Lochcarron.