Author Topic: Question about video signal...  (Read 826 times)

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Offline sam1275

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Question about video signal...
« on: September 26, 2016, 11:29:50 PM »
Hi everyone.
I had a Armasight digital night vision monocular and then the eye piece optics brokes, I can still see the output from the very tiny LCD, but I decided just to reuse the sensor part.

I took it apart, and found the "main" board is very simple, just some regulators and capacitors to distribute the power to the sensor board and the LCD board. The main video processors are all on the sensor board, and there are only 3 lines connect to sensor board: 2 are powers, another must be video signal, which goes through a potentiometer and then to the LCD board.

But now the problem:
1. It's only one line for the signal, so I think it must be composite signal, but is it possible to adjust the brightness just by a potentiometer on the signal line? I mean, from complete dark to a extremely sensitive(much more sensitive than human eye, with lots noise), I think that should be some settings to do with the sensor and DSP, not the output signal...
2. The factory voltage on the sensor board is 7.86v, but I connected a 9.3v adapter to the board and hook a monitor to it, nothing output, did I burn it up or it's just not a composite video?

I took pictures of the board:



Thank you!
« Last Edit: January 11, 2017, 01:06:20 AM by sam1275 »
 

Online PA0PBZ

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Re: Question about video signal...
« Reply #1 on: September 26, 2016, 11:55:01 PM »
Pin 75 on the CXD3142R switches between PAL and NTSC, HIGH = PAL, LOW = NTSC. Looking at the pcb I think the pin is HIGH.
Maybe your monitor doesn't like PAL?
Keyboard error: Press F1 to continue.
 

Offline bktemp

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Re: Question about video signal...
« Reply #2 on: September 26, 2016, 11:56:13 PM »
The board looks like a ordinary camera module and the CXD3142R outputs a composite video signal. Therefore it is most likely a composite video output.
Maybe it needs AC coupling or a termination resistor to GND or a high impedance buffer.
 

Offline technotronix

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Re: Question about video signal...
« Reply #3 on: September 29, 2016, 04:47:15 PM »
No, It doesn't look like burned. I think it is a composite video only.
 

Offline sam1275

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Re: Question about video signal...
« Reply #4 on: January 11, 2017, 01:05:55 AM »
Thank you everyone, I just confirmed that my monitor do support PAL, I also tried another device with AV in, still no signal.
I think maybe it have some special design that not compatible with a normal composite monitor?
 


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