Hi my name is Dave and my hobbies include marine fish keeping. I currently have a refractometer (for measuring salt). Currently I manually add a few drops of salty water to the sloped end of what looks like a telescope. I then observe the reading form the other end.
Where the white and blue meet is the current salt level.
So my question is can I build an electronic version, one that can turn the reading onto an electronic number that i can just glance at. Also if it could have some way of turning on a switch if the level gets too low (one that I could set too a certain level).
A way I thought of doing it would be some kind of photo sensitive diode at the reading end and a light at the other end and the amount of resistance would determin the level of salt in the water. I would however think that this would have to be very sensitive and I would imagin as the bulb ages the light levels would alter the results so maybe a laser.
Any help would be much appriciated and if you need any clafication I will try my best. It might be easier to have a usb socket so I can adjust sensitivity etc.
Dave
Where the white and blue meet is the current salt level.
So my question is can I build an electronic version, one that can turn the reading onto an electronic number that i can just glance at. Also if it could have some way of turning on a switch if the level gets too low (one that I could set too a certain level).
A way I thought of doing it would be some kind of photo sensitive diode at the reading end and a light at the other end and the amount of resistance would determin the level of salt in the water. I would however think that this would have to be very sensitive and I would imagin as the bulb ages the light levels would alter the results so maybe a laser.
Any help would be much appriciated and if you need any clafication I will try my best. It might be easier to have a usb socket so I can adjust sensitivity etc.
Dave