Hey, I am looking at getting a multimeter for a project I'm doing. I found from a shop here for just under $10 which is a good price for a new one. I don't know how to use it yet but I can learn The one I am looking at is here, http://www.dse.co.nz/cgi-bin/dse.storefront/424f6b5f0aa75abc273fc0a87f99072e/Product/View/Q1469. Will this be alright for general pc modding use? Just wondering, in this pic, are those 2 leads thingies for doing it with led's do you put one stick on each leg of the led? Is that how it works? Cheers
hmmm, i cant really think what you'd be measuring on an led [but then again, im certainly no wiz]. for something simple like the resistance of a resistor, you would put the dial on the level you think might be appropriate, and then put the one lead on each end of the resistor. i wouldnt be at all surprised if there's a how to on multimeters in the stickies at the top, or at least somewhere on the net.
There's a diode test setting between 200 ohm & 9V which will tell you if a led is broke or not, and which leg is which. Same setting will test for breaks in a circuit.
Can I use it to check the voltage of led's? Because I'm swapping the power and hdd led's in the case for orange ones and I want to get ones that are the same volts.
umm, you can set it to test for voltage, and then _carefully_ touch the separate leads or solder points of the LEDs you will be replacing. Most standard 5mm (T1-3/4) use 5V. Just make sure you don't short the test leads to anything else, otherwise you might let the magic smoke out and ruin something important/expensive!
Okay, so I just put one of those sticks on each leg of the LED. What setting do I have it on on the multimeter? Thanks for your help _b
well, the symbols are usually pretty universal, so it's most likely something with a V or like Vcc. Check your manual though, just to be on the safe side, and to make sure you use the right connection points for the test leads.
Okay, a few basic tips for multimeter use. For measuring Volts (V range on the meter), if you know the approximate voltage to expect (in computers typically 5 & 12v) you'd set it to the 20 Volt range, and put the probes on either side of the part you want to see the voltage across (red is the positve probe, black the negative, but if you have them backwards, you'll get a negative sign on your meter). When testing unknown voltages or current....set your meter to the highest range, and switch ranges down till you get a good reading, as you can see the ranges go in a sequence like 0.2 (200 millivolt) 2, 20, 200 on the volt range, the max reading on any range is 1999 not 2, so if you had a reading of 12 you'd set it to the 20 range so that one of the MSD (Most Significant Digits is in use), if your reading is 5 volt then you again would have to use the 20 range, as it exceeds the reading on the lower 2 range. (sorry if this is 2 basic for you) For measuring current (A range on the meter) you need the meter to be in series with the circuit, for example with your LED you would dissconnect one lead from the led, connect one probe to the led terminal, and the 2nd probe to the dissconnected lead, again switch down the ranges till you get a good reading.. For resistance (ohms range, signified by the Omega symbol,bottom left on your pic), measure across the resistor, where i have said start with high ranges for current and voltage, this isn't neccessary here, if the resistor is over the range you have the meter set on you will have the far left digit flash 1 to show overrange. The reason for starting on the high ranges and switching down, is from the pre digital days, when the fast way to kill a multimeter was to zap the coil meter movement with a higher voltage or current than what would give FSD (Full Scale Deflection) of the movement, modern meters should be more robust, but a being careful in the use of our tools means they will be functional for a long time to come. As a quick note on LEDS, it is not the voltage that you need worry about, it's the current that gives the brightness, different colour leds run at different currents, and changing the resistor attached in series with the led will increase or decrease the brightness, there are data sheets for most leds, and if the current range is known, then the required resistor can be calculated using the voltage it will be connected up with. R (resistance) = volts /current hope this helps a bit
Thanks for that post man, that's just what I needed Can you have my babies ? On the site for this multimeter, it says: # AC Voltage: 200mV⁄200V⁄300V # DC Voltage: 2000mV⁄20V⁄200V⁄300V # DC Current: 2000uA⁄20mA⁄200mA # Resistance: 200Ω/2000Ω/20kΩ/200kΩ/2000kΩ I don't see a 2V one there, can I use 20V to find voltage of LED's if they are under 2V? Or is 2000mV the same as 2V? The LED's I'm buying are DC FORWARD VOLTAGE:1.7V TYPICAL DC FORWARD CURRENT:20~30mA I suppose mV is millivolts?
