I have very little experience with electronics so I have come here to hopefully gain your insight into an issue that is currently being discuss amongst people who seem to have no clear answers. The circuit I am interested in utilizes a 9V battery run through a LM334Z current regulator, with a 33ohm resistor to limit the output of the device to 2.0mA . Can and do these components fail and what is the probability of failure considering only a 9V battery as a power source? Are there better components to use? Any empirical references to component failure would also be appreciated. Hopefully that will be enough to get the subject off the ground. Thank you.