I designed it, Tracecom built it, he says it works.
One (9) volt battery and a MAX6035 create a constant current of 10.00 ma.
Your meter on a 200 millivolt scale will show numbers like 199.9 which means 19.99 ohms. Good for those 2 watt emitter resistors like, .15 ohms or .27 ohms.
You can change to the 2000 millivolt range which will show 1999 and mean 199.9 ohms.
The chip needs 4.75 volts, so the high limit is about 245 ohms, showing 2.45V on a 20 volt scale. You can get to about 425 ohms (4.25 volts) if you remove the LED.
Using only one battery and 3 electronic parts makes this fairly inexpensive.
You can build the adapter or just clip your voltmeter on to the leads of the Device Under Test. Just be sure to place your meter connections closer to the body of the resistor than the current driver alligators.
One (9) volt battery and a MAX6035 create a constant current of 10.00 ma.
Your meter on a 200 millivolt scale will show numbers like 199.9 which means 19.99 ohms. Good for those 2 watt emitter resistors like, .15 ohms or .27 ohms.
You can change to the 2000 millivolt range which will show 1999 and mean 199.9 ohms.
The chip needs 4.75 volts, so the high limit is about 245 ohms, showing 2.45V on a 20 volt scale. You can get to about 425 ohms (4.25 volts) if you remove the LED.
Using only one battery and 3 electronic parts makes this fairly inexpensive.
You can build the adapter or just clip your voltmeter on to the leads of the Device Under Test. Just be sure to place your meter connections closer to the body of the resistor than the current driver alligators.
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