Hi Leonia, I've reloaded the data and there is still a problem as Jim described. Flagging the time range he suggested does not fix the problem. Please could you take a look at it? The data are on /DATA/TIGUA_1 and the problem only seems to arise with the channel 0 data, 19980420.CH 0.1 suggesting some problem in FILLM... My user number is 1950. Claire