Why can't I get power to my rf modulator?

Question

When I plug in my rf modulator, the led light will flash for a second and go off. For some reason I cannot get the power to stay on. I bought another one and the same thing happens. What could the problem be? Then, all of a sudden it will work, and when I go to use it again and it won't. I just can't understand how this could happen with 2 different kind of modulators.Is there any way of fixing this problem.

Answer 1

Some modulators require a signal to be present to turn on. Feed a signal to it and see if turns on then.