- Limiting operations with a light sensor -


After repeated checkings, I found that my solar battery was steadily being
depleted. Not a lot, but still not even breaking even. I also have to admit,
that we had overcast a lot in the past couple of days... Depletion
unfortunately means, that somehow the camera consumes more energy
than the solar panels can produce... Had to investigate :

Turns out, that the camera is drawing a constant 230+mA, no matter
what. After logging in and looking at the running processes, it seems
that the CMOS image acquisition process is running all the time.
This is understandable if motion detection or quick response time is
needed, but for me ( I can wait a second ) this was a problem :



Since Asante refused to give access to the source code,
( running Linux, mind you, they should by law obliged to release )
I couldn't tailor the behavior of the camera from software.
As an engineer, I had to turn to hardware to solve the problem.
As the camera would be working at full power even at night,
the least I can do is to put together a circuit which would turn
off the power to the camera during dark-hours :



Using a breadboard is great for developing prototypes :



Now, under low-light conditions, we only use 10mA :



I weather-proofed the circuit :



Interrupted the power to the camera with this new circuit :



Hopefully the solar panels now can cope with the camera.
That red light means that the camera is currently off :


Go back to the Voyager I page.