Night Vision in Car

**shotgunefx** · 02-21-2006, 08:32 AM

Originally Posted by quantum

So...where the ground go?

...
The Nitemax does need some kind of 12V negative ground, but where o' where do it go?

Any reason you're not just tapping off of the barrel connectors?

**quantum** · 02-21-2006, 09:48 AM

Cus I don;t know where the barrel connectors are.

I understand the 12v + lead, but the ground is throwing me. Like I said, my best guess is it goes to the RCA connector (outside) and them off to the CN spot on the board.

If someone could help on this one, I'll buy lunch. I don;t want to fry the NiteMax.

**shotgunefx** · 02-21-2006, 09:59 AM

Originally Posted by quantum

Cus I don;t know where the barrel connectors are.

I understand the 12v + lead, but the ground is throwing me. Like I said, my best guess is it goes to the RCA connector (outside) and them off to the CN spot on the board.

If someone could help on this one, I'll buy lunch. I don;t want to fry the NiteMax.

Confused... Did you forget where the DC-IN hooks up to? Or are you trying to eliminate the board it hooked up to?

**quantum** · 02-21-2006, 10:45 AM

I don't think I know where the DC in hooks up to.

The DC in jack is tip positive. That lead goes to the switch and feads down to the board with the battery on it. I got that part.

But, in the car, I will have 2 lead, + / -. So, the negative lead neads to attach to something, but I can't figure out what. I am guessing here, but could the CN on the board stand for Composite Negative???

The way I trace what I think is the ground...there was a solder point on the outside of the DC IN jack. It had a short length of wire that went to the outside of the RCA jack. Then another length off that solder point that went to the switch board on the left side (back facing you). It then came out the other side (2 leads on the push button back) and was soldered on the the CN point on the square board.

Working off the camera battery, it works fine. My concern is hooking it up to the car. maybe I am looking at the wrong board? Do the 12v go to the board with the battery on it instead??

**shotgunefx** · 02-21-2006, 11:34 AM

Originally Posted by quantum

I don't think I know where the DC in hooks up to.

The DC in jack is tip positive. That lead goes to the switch and feads down to the board with the battery on it. I got that part.

But, in the car, I will have 2 lead, + / -. So, the negative lead neads to attach to something, but I can't figure out what. I am guessing here, but could the CN on the board stand for Composite Negative???

The way I trace what I think is the ground...there was a solder point on the outside of the DC IN jack. It had a short length of wire that went to the outside of the RCA jack. Then another length off that solder point that went to the switch board on the left side (back facing you). It then came out the other side (2 leads on the push button back) and was soldered on the the CN point on the square board.

Working off the camera battery, it works fine. My concern is hooking it up to the car. maybe I am looking at the wrong board? Do the 12v go to the board with the battery on it instead??

I've got one mostly apart, but not the lcd driver so I cant' see it. (I'll try to check later).

But the dc-in is 2 wire as well, tip + / barrel negative, so instead of trying leads, why not just solder to where the jack leads are, or just buy a tip at radio shack and that way you an uplug it if you need to do something to it?

On a related note, I noticed on the front board (that the cam plugs into), there are two lm2941s adjustable voltage regulators. I don't have time right now to figure out what voltage they're driving. I also wonder why there are two. One for battery and one for dc in? Or maybe two different voltages. I dunno.

I would think if they are driving the boards and wired as a vreg, then changing the input will change the output. So going with 12-14v might not work out so well.

**NiteMax Mark** · 02-21-2006, 11:55 AM

Originally Posted by shotgunefx

I've got one mostly apart, but not the lcd driver so I cant' see it. (I'll try to check later).

But the dc-in is 2 wire as well, tip + / barrel negative, so instead of trying leads, why not just solder to where the jack leads are, or just buy a tip at radio shack and that way you an uplug it if you need to do something to it?

On a related note, I noticed on the front board (that the cam plugs into), there are two lm2941s adjustable voltage regulators. I don't have time right now to figure out what voltage they're driving. I also wonder why there are two. One for battery and one for dc in? Or maybe two different voltages. I dunno.

I would think if they are driving the boards and wired as a vreg, then changing the input will change the output. So going with 12-14v might not work out so well.

I am sorry I haven't had time to weigh in on the power connection stuff (yet) but you might end up hunting down the ground connection before I do!

The power supply has a DC-DC converter that takes the battery voltage or AC/DC Adapter voltage and boosts it up to 13 volts or so. One LM2941 is rigged up to produce 12 volts for the CCD and the LCD Controller. The Other LM2941 is controlled by a digital potentiometer to power the IR LEDs with varying intensity. The LCD Controller regulates its own 5 volts for internal use as well as providing a reference for the LCD Contrast digital potentiometer.

The ground connection gets soldered to the LCD Controller as I recall. Then it is provided to the Power Supply Board through the 15-pin cable. (Not too smart in my opinion) Your best bet is to solder your ground wire to the negative end of one of the three large black capacitors on the Power Supply Board. Or, solder your ground wire to the same point as the CCD's ground wire.

**skymann** · 02-21-2006, 04:28 PM

thanks .. really exciting

**0l33l** · 02-21-2006, 06:28 PM

Originally Posted by shotgunefx

First thing you'd need to do is get a board camera lense. Check out ebay ~ $10-15, but most of the ones I see there have an F-2, as above, not that great for IR, but I have a feeling most reverse cams are the same.

You'd need to find or make a threaded mount for it though.

Looks like another project for me

**shotgunefx** · 02-21-2006, 06:37 PM

Originally Posted by 0l33l

Looks like another project for me

That's what I'm doing with one of mine, a nice wide angle lens like the rear cam. I'm going to mount it in front of the rear view mirror. A CS lenses is a bit big for the space.

**0l33l** · 02-21-2006, 06:41 PM

Originally Posted by shotgunefx

That's what I'm doing with one of mine, a nice wide angle lens like the rear cam. I'm going to mount it in front of the rear view mirror. A CS lenses is a bit big for the space.

Haven't gotten my lens yet, so I don't know. I got a 2.8mm one with a 130deg angle and its f1.2