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    Artificial Intelligence

    For the climate deniers lets put you in a shipping box for a refrigerator, then light a small candle inside box. We will come around in an hour to see how you are doing in that climate change environment, driven by CO2. By the way, message me with your contact info so I can send you mine to put...
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    How to connect this strain gauge?

    I did a sim, but AD620 spice model has a problem allowing a connection to Vref pin. So I have contacted Analog Devices to see if I can get this rectified. Basically R2 is swept from 120 to 140 ohms. Regards, Dana.
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    How to connect this strain gauge?

    What does you schematic look like now. Your DMM, just the LSD flickering ? Battery good in DMM ? Regards, Dana.
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    How to connect this strain gauge?

    Remember you are working with a straight line transfer function with an offset. These settings interact with each other. But we know how to fix the G, discussed above, now we have to get the offset right. I am going to leave for awhile, get a pic of your power supply adapter output. Many of...
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    How to connect this strain gauge?

    Remember to add a R between A/D input and AD620 / last opamp you are using to prevent overdriving A/D input and damaging it. Say for now 1K to 2K. What does your schematic look like now ?
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    How to connect this strain gauge?

    You need to set the G, not with a pot, but a fixed R. So we have a design deviation of +/- 100 mV, and we want the slope of a straight line into A/D, when at +100 mV, to generate 5V. So what is that G ?
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    How to connect this strain gauge?

    Great scope, so in display mode set it to AC, 1V / div, infinte persistence, sweep rate of say 1 mS / div, norm trigegring, trigegr set to edge, say 50 mV, and what do you get for peak to peak noise. Let it run in that mode for a minute or two before you take the visual reading.
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    How to connect this strain gauge?

    So I would run the strain gauge off 5V with a series R of 120 ohms to its + power lead. Thats 20 mA thru bridge. Then use diamond tool to find what Vref you need and G setting for 620 to get 0 - 5V out of it. For a +100 mV deviation in the bridge and 0V for a -100 mV deviation.
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    How to connect this strain gauge?

    Currently what is the AD620 G set at ?
  10. D

    How to connect this strain gauge?

    I would run the strain gauge off 5V, the AD620 off 9V. That would put 40 mA thru strain gauge, what was the max allowed current ? If thats too much current power off 9V with a series R to limit current to spec. Or use a low voltage zener. This all has to be simed out to see what range you get...
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    How to connect this strain gauge?

    Your jumping values, do you have a scope ? I suspect what you see is the power supply noise from the adapter. With a scope on infinite persistence you can see what pk-pk noise is on a power supply rail. 100 - 200 mV of noise OK in a 5V system, most designs. Depends on what you are doing...
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    How to connect this strain gauge?

    Short answer is NO, you wont have enough range to make as good solution. The range would only be ~ 1V due to the limited output swing of the AD620 running off 5V. But the Arduino can switch its reference to ~ 1V, so a design could be done, but more design and simulation work has to be done. I...
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    Toob to transistor conversion

    There are folks in Amatuer radio that have converted shortwave receivers to transistor using some of the components (but few), like IF Transormers and tuning caps and some coils. But it really is a ground up design, not a simple task, to do it right. This gent has done seval : Example...
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    help with a 12v control circuit

    Author of circuit unknown : Regards, Dana.
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    Power Calculation

    P = E**2 / R = R = (100 + 2), V = 600. I = V / R = 600 / 102 Pswitch = I**2 x R = (600 / 102 )**2 x 2 ohms = Regards, Dana.
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    How to connect this strain gauge?

    No, I missed the module link. That module has a negative supply generator on the board, and an opamp to do the offset. All you do is connect the sensor to module, and adjust the G and Offset pots to get the 0 - 5V (or 3.3V) range for the Arduino input. Keep in mind the pots will interact in...
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    How to connect this strain gauge?

    Sim for -V generator, you will have to juggle values to get AD620 output swing down to 0V (to maximize Arduino A/D input range). Also use Schottky diodes versus the Si I used, to get more - V. Basically strive for ~ 2V so that AD620 can swing to ground. Note using Schottky's versus IN914 should...
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    How to connect this strain gauge?

    The gauge circuit is driving the ground, in this case, of the Arduino which would pose additional problems interfacing to it. You have a bridge, connected to Vcc, lets say 5V. Its CM V is 2.5V. Its deviation you have to compute, but for this example, when bridge unbalanced ranges +/- 100 mV. So...
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    How to connect this strain gauge?

    Tha allowed Arduino input range is 0 - Vcc, Vcc is either 3.3 or 5V. So you cannot overdrive the input. Circuits you can use to accomplish this : https://electronics.stackexchange.com/questions/35807/how-would-i-design-a-protection-clipper-circuit-for-adc-input The Ad620 has to be operated at...
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    Artificial Intelligence

    If AI understands the concept of survival the first thing it will do is wipe out any species that is either incapable of self preservation or is an active participant in killing/destruction of itself or like species and/or the destruction of planet..... That would be humans.......on all the...
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