Tailhappy

Hello, I'm trying to extract a little more life out of my PC based video monitoring system by upgrading to a 720 TVL camera (Bosch TVL-206). I had hoped it would be simple matter to unplug the existing B&W cam and plug in the new camera. This plan failed miserably, but I'm looking for hints as to why I get a black screen with the new camera and what I can try. Using ZoneMinder software and lorex capture card. I've tried modifying resolution from 384x288, but regardless of new res value, no scanlines appear at all. Is there any chance this cam can be made to work? I understand how much better digital systems are, but until my living arrangement stabilizes, the best solution is to milk the analog cams for now. Thanx.