Pipe camera locator activation

[DC Jack]

Hi everyone,

I'm playing around with one of those pipe cameras systems that has dead video and it has a spare head from a different model, so dramatic modification will be needed.  I have been bench testing the spare camera head and everything seems to work.  It has four connections (Gnd, 12v, Composite video, LDE brightness adjust) but I can't figure out how to activate the location signal.  I have figured out that it is using something called a Sonde locator and that machines have a momentary switch on the base station somewhere that deactivates the CCD and activates the Sonde 512hz signal so it can be located and in turn know where a supposed pipe blockage it.

Anyone here know their way around these camera heads?  I'm guessing it's either a signal like a IR remote, or a pull up/down of the video line.  I have no experience with these so I'm asking around here before I start to destructively digging into the dead camera as it is a sealed system to make it waterproof.