Can someone modify this retro circuit for Night vision Binoculars

I've had this Newcon Optik night vision Binoculars which I used when I was little.
Today I found those again in my junk stuffs, they've not been used for around 8-10 years, were working before.
I tried basic troubleshooting, checked if the ON switch is working, voltage to the Board etc.
I just have basic, very basic knowledge about Circuits.
I'm attaching photos of the PCB and components,
If anyone's able to help then I can provide more information required.