Recent content by epcole

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    How to calculate the Resistor Values for an op amp circuit

    I need help calculating the R values for this circuit from the following article: AN HIGH RESOLUTION RESISTIVE PROBE FOR NONLINEAR ANALYSIS OF TWO-PHASE FLOWS L. Cantelli, A. Fichera, A. Pagano This is only a section of the circuit, there is more but I'm only interested in this part of...
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    Can I get +5/-5vdc from 9v battery

    Using TL084 and want to supply +/-5v for power. I heard there is a way to do it with 9v battery but I can't find any info. anybody have an idea on how its done? thanks
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    Weird Oscillation in wheatstone bridge circuit

    I have this weird oscillation coming from my circuit. its a wheatstone bridge with a single strain gage. I am using The PST 4130 from Omega Engineering to supply +10vdc. When I first turn it on the signal is pretty clean, but after a while, it turns into this...
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    My IEC Contactor Coil keeps overheating

    I have a 3ph IEC contactor with 120v coil voltage. For some reason, the coil starts heating up like crazy when I run it. I have 121v on L1, 120v on L2 and 121v on L3. I re-connected all the wiring to make sure there were no loose connections but still it keeps heating up when I energize the...
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    How can I add an end switch to carraige system

    I have a carraige being operated by a transmission drive on a 120v 3ph 2hp motor. I am using a magnetic contactor, followed by a reversing drum switch (a later addition when they didn't want to push the cart back after each run). Now they want to add a switch down by the end of the tracks to...