Hi Alan B. Pearce, thank you for your answer. Thus, you mean that with a simple analog oscillo= scope (CQ5020F) we can't have a stable low frequency signal (like 10hz...).= I want to be sure of that because I am trying different settings on my osc= illoscope in order to stablize the signals on the screen in vain. thank you in advance, best regards, Mustapha ELKEJBOUT --------------------------------------- "Every one has to do what he can do according to how it can be truly done" For whom the bell tolls, Ernest Hemingway. = --------------------------------- D=E9couvrez une nouvelle fa=E7on d'obtenir des r=E9ponses =E0 toutes vos q= uestions ! Profitez des connaissances, des opinions et des exp=E9riences de= s internautes sur Yahoo! Questions/R=E9ponses. -- = http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist