hi everyone, sorry to bother you all with this idea but it seems to have gone beyond my knowledge.
i have a light, this light is on all the time, but it pulses very briefly where it gets a bit brighter. i am using a light dependent resistor to try and detect these pulses and turn them into an on/off signal that i can supply to my micro processor.
now what i have tried is to use a transistor, but that didn't work because the light is on all the time, there was a small voltage getting through which caused the transistor to be partly on. i tried putting a resistor between the LDR and the transistor but that stopped the transistor from working at all (it was a veriable resistor so i could test all resistances)
then i tried a reed relay, the LDR kept the reed relay on all the time, so again i used a resistor to bring it down until it was just off, but this didn't work either, the change in voltage is just too small.
if i run the LDR straight to an LED, it is possible to see the pulse, so it is making a difference, but it seems to be so small that i cant detect it with anything and turn it into a square wave.
i tried a darlington pair for the transistor, but the transistor was still semi on.
i am sure this should be a simple fix, but i am at a loss. any input would be really appricated, thanks everyone!
i have a light, this light is on all the time, but it pulses very briefly where it gets a bit brighter. i am using a light dependent resistor to try and detect these pulses and turn them into an on/off signal that i can supply to my micro processor.
now what i have tried is to use a transistor, but that didn't work because the light is on all the time, there was a small voltage getting through which caused the transistor to be partly on. i tried putting a resistor between the LDR and the transistor but that stopped the transistor from working at all (it was a veriable resistor so i could test all resistances)
then i tried a reed relay, the LDR kept the reed relay on all the time, so again i used a resistor to bring it down until it was just off, but this didn't work either, the change in voltage is just too small.
if i run the LDR straight to an LED, it is possible to see the pulse, so it is making a difference, but it seems to be so small that i cant detect it with anything and turn it into a square wave.
i tried a darlington pair for the transistor, but the transistor was still semi on.
i am sure this should be a simple fix, but i am at a loss. any input would be really appricated, thanks everyone!