Hi,
very very thanks for your kind answers.
So, I desoldered everything ( 
) and tested it again on the breadbord.
Now I could measure the resistance of the Flexiforce sensor correct : It is very high as I assumed, higher than my meter can measure (5-10 MOHM as the datasheet says).(there was a short circuit under the sensor with the frame I think why I measured the wrong resistance of 1 MOHM)
Then I tried an resistor with 100 KOHM as the extra resistor and wired it exactly as shown in the photo above from the tutorial:
Nearly the same result as with the 1 MOHM resistor, at no load 0 V, with 600g 3,8 V both shown on the serial monitor and measured with my multimeter.
I worked very accurate and I think nothing could be wrong, all as in the tutorial and nothing other is connected.
The code is the original from the tutorial.
Still not possible?
The only difference is that the raise of values is much more linear than with the 1 MOHM resistor which is very good and so it was very good to dismantle all and wire it new!
I will try other resistors now and watch if I can get a better linearity.
Because you dont believe it I made 2 photos of it I hope you can read the output of the serial monitor.
Thanks for your kind help..
Ralf
