Are you trying to wire up a 'regular' analog video camera or a high-definition one? I googled Nighthawk but couldn't find anything.
Most passive video baluns use two wires and send analog video over hundreds of feet of cable.
Some of the newer baluns for high-def cameras might use more than two wires, i dunno. I don't do it that way.
With the limited visibility you will experience even in really clear water, caused by the water absorbing all the red part of the spectrum, and all the particulate matter floating in front of the camera, and light pollution/ backscatter from your led lights reflecting back into the camera lens from all that fine floating crud, you won't really get any better video from a high-def camera than you would from a cheap analog one. I use alot of these...
https://www.banggood.com/Eachine-1000TV ... rehouse=CN
And for the main camera looking forward w/ pan-tilt-zoom, i use a Panasonic SDR T55 camcorder. I bought it used off eBay for $40. It sold for $300 new. Looking recently i see SDR T50's available, they have the same 78-power optical zoom. That allows me to zoom in as close as i like. It puts out a regular composite video signal.
To get the video to the surface i use a cheap 8-camera security-system DVR onboard my ROV. This allows me to have 8 camera feeds multiplexed through the DVR, connected to the same wired ethernet switch my Raspberry Pi is, then to a (used, eBay) DSL router, that communicates with the surface DSL router/computer over a two-wire tether. 8 camera feeds plus full control over my ROV via just two wires. 14 awg speaker wire.
If you want to take 12MP photos that you can review later, just mount a Firefly Q6 camera coaxially with the camcorder. It's tiny and about $58.
All of these components are powered by onboard batteries. My ROV is the size of a large ice chest. As i posted in another thread just this morning, i find that small ROV's get moved around/ jerked by the tether and you end up with poor video. The bigger/ heavier it is the more stable it is. I have a truck, but even so, someone with a Toyota Corolla could pull a small cheap Harbor Freight trailer.
