zero cross detector

hi

i already built a zero cross detector using the IC LM311 ,and the circuit is based on a schematic on www.national.com on conventional positive feedback .

the problem is the sine wave change when i turn on the zero cross detector. does this effect the accuracy of the data i am taking? if it do, how do i fix this problem .

any advice is appreciated,thanks

dark_conqueror

Do you mean that when you are using your detector it is affecting the signal you are using to drive it. If that is the case, then you probably need to buffer the signal with an amp as the impedance of your detection circuit is too low.