hi,
I'm getting weird readings on one of my DMM's when testing diodes.
E.g. I'm using USB power, the DMM (in Vdc measurment mode) read 5V, I insert a 1N4007 between the positive probe and positive pin of USB, and instead of getting a lower reading because of the diode's voltage drop I get a higher one, 6V. When I flip the diode, i.e. insert it reverse biased I still get a reading and it's -1.2V.
I've tried another DMM with the same setup and get the expected results, i.e. voltage drop when the diode is forward biased and 0 volts when reversed.
Is the first multi-meter busted? Any ideas?
I'm getting weird readings on one of my DMM's when testing diodes.
E.g. I'm using USB power, the DMM (in Vdc measurment mode) read 5V, I insert a 1N4007 between the positive probe and positive pin of USB, and instead of getting a lower reading because of the diode's voltage drop I get a higher one, 6V. When I flip the diode, i.e. insert it reverse biased I still get a reading and it's -1.2V.
I've tried another DMM with the same setup and get the expected results, i.e. voltage drop when the diode is forward biased and 0 volts when reversed.
Is the first multi-meter busted? Any ideas?