Hi guys I know I have already asked the question but, I am having problem generating noise source in a practical circuit. According to some advice i recently got, i tried using a zener diode in a reverse biased direction and inputting it to the negative terminal of an op amp while keeping the positive terminal grounded. I did not see any trace of noise source in the oscillloscope. Can anyone tell me whether the process i am applying is wrong and if so whether there are any other ways of doing it? Thanks a lot