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I saw this auction in the ebay deals thread and put a low bid on it. I won! $34 shipped. The external cable has red/black/white/green/drain and is a 5-pin connector. I took the back off (just two allen bolts). There's an op-amp, two local regulators (those TO-92's), and a bunch of passives. Only 4 of the 5 connector pins are used. I traced out the paths and found +, -, gnd, and output pretty easily.
Looking at the datasheets for the two regs, they're +/- 12V with 1.7V dropout at 40mA. So I suppose that means it wants +/- 15V in. Any lower and it's not in regulation. Any higher and the voltage gets dropped anyway. I hooked up a pair of bench supplies and checked the output which sat at 1.4mV. I pointed a beam at it - it's alive! I compared readings with my analog Gentec meter. They're within ~2% of each other with both a 280mW red and a 1.8W blue. The scale is 1mV/mW.
But my question is: is this a 40W sensor? The water lines suggest so, but the local 12V regulator and the mV/mW scaling suggest it only goes to 10V or so (10W). Google hasn't been helpful.
And what about those standard 20W ophir heads everyone gets? With a 9V supply, how can those go to 20V on the output? Surely I'm missing something simple.
Looking at the datasheets for the two regs, they're +/- 12V with 1.7V dropout at 40mA. So I suppose that means it wants +/- 15V in. Any lower and it's not in regulation. Any higher and the voltage gets dropped anyway. I hooked up a pair of bench supplies and checked the output which sat at 1.4mV. I pointed a beam at it - it's alive! I compared readings with my analog Gentec meter. They're within ~2% of each other with both a 280mW red and a 1.8W blue. The scale is 1mV/mW.
But my question is: is this a 40W sensor? The water lines suggest so, but the local 12V regulator and the mV/mW scaling suggest it only goes to 10V or so (10W). Google hasn't been helpful.
And what about those standard 20W ophir heads everyone gets? With a 9V supply, how can those go to 20V on the output? Surely I'm missing something simple.
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