Thank you, but for me, the new sleepanalyser (1.9) never wake me up before the alarm. The blue line is always far below trigger level (20).

Please have a look on the attached pictures.
You have to adjust the blue graph (in settings window), so it looks something like on the picture. Most of the time, I was in deep and light sleep, but sometimes I also moved around a lot which could be interpreted as being awake. If the blue is always is the upper half, then you might have to lower the scale value.
After that, set the trigger level to somewhere around upper part of light sleep or awake.

On the 2nd picture you can see the improvement with the new trigger algorithm. Before you would already have gotten woken up at the first yellow spike, now it takes a bit more. With the new algorithm I hope to have improved the way it detects the right wake up time.

If you are struggling to get it working, please post a picture of your record here and we can try to help adjusting it.
In case you are not aware of it, SleepAnalyser has a nice export function to export the graph a you can see it on my pictures.

Hmm my yellow lines don't seem to go as high as yours, apart from when I'm actually awake. Should I put the phone closer to me? It's currently under the pillow next to my head.

There is also a setting to set the scale of the yellow bars.
Actually it only changes how much they are stretched on the graph and does not change anything on the trigger level or blue graph.

I also have my phone under the pillow, so thats fine.

It just depends on how much you move during you sleep. I usually put it to the side of me (right next to / just slightly under the pillow). I actually do notice a significant difference depending on how far exactly the N900 is from me, but that's also largely a bed thing too - different beds have different springs/mattresses/supports/etc, and will thus convey movements more/less.

I try to change the blue and yellow value but without success.
Note that even when there is lot of movment, the blue line is
below the trigger level. I put the N900 on the mattress under the sheet (i can't put in the pillow).

whats your values for the scaling?
put the blue one to the maximum.
.the yellow ones seem to be streched a lot indeed.
can you attach the record vile, so i can play arround with it myself?
my current settings are:
yellow: 2
blue: 33

Values : 7 (yellow) and 45 (blue)
Yes thank you. Here is the file ...

Hi Guyr

It seems that you either almost do not move during your sleep, or your mattress is very hard or your phone is too far away.

I modified SleepAnalyser a bit. You now can change the Y scale value (blue) up to 120.
Because of that you will always be in light sleep and almost never in deep sleep. To correct that, there is a new value, Y offset (blue). For your case I suggest to put it to 35.

I am not sure how good this will work, so please give feedback/screenshots after a few nights.

I move a lot during may sleep, so i think my mattress is hard and the phone is not close enough ...
But with blue (120) and offset blue (40) i get beautiful graphics and i'm very happy with that.
However, with these settings the alarm do not sound even if the blue line is very high (top of the graphic) ...
I give you some feedback after a few nights.
Thank you very much.