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    DC Panel meter read errors on charger

    It would be worth while for "meter users" to read a few of these App's note's... http://store.cd4power.com/cgi-bin/cd4power.storefront/44ef513100171934271d0c9f89420625/Catalog/1120
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    Constant current source for a low Ohm load

    I've never built that particular circuit, but have built very similar circuits. Unfortunatly, the easiest way to measure current it to put it through a resistor and measure the drop. You indirectly bring up the age old question of... how good is good enough!! Since there will ALWAYS be "some...
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    Choosing the right equipment wire?

    http://www.interfacebus.com/Copper_Wire_AWG_SIze.html
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    Choosing the right equipment wire?

    The "ampacity" of wire is based on temperature rise. Different types of insulation on the same wire AWG will have different ampacities. It really comes down to how much drop can you tolerate. If you need to be "legal" in the regulatory agencies eyes, there are "tables" that specify allowed...
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    Constant current source for a low Ohm load

    Why not try something like this...
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    Do my needs come in surface mount?

    Check out Philips for the semiconductors, the passive devices you can get almost anywhere.
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    Using Thevenin's theorem on Wheatstone Bridge

    Does it have to be with Thevenin's? Try it with a "delta-Y" transformation..........
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    What are discaps?

    It's a  monolithic ceramic disk capacitor.
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    Cell Phone "AA" BATTERY Replacement...

    Be careful here... Yes, it's a boost converter, but by definition, a boost converters output will always be bigger than it's input. Just because it says the input range is to 5V, doesn't mean you can put 5V in and get 3.7V out... won't happen. Your input voltage would have to be less than 3.7V...
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    Fixed current power supply 100A DC

    But 1 micro ohm and 100A gives you .1mV. You said you have a mV meter. Seems like a better meter would be an "easier road", than the cost and trouble of constructing a 100A source (these current levels are not easy to deal with). Contact resistance and wire IR drop come into consideration...
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    What is a voltage regulator?

    I don't see NewToElectronics mentioning/asking anywhere about powering a cell phone, but anyway... First, a DC-DC converter works by "chopping" the input DC voltage into a square wave, it's not a "sinusoidal a/c source". There are a few things to consider when doing "this" with a DC-DC...
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    High frequency A/D

    What do you consider high frequency?
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    Tunning

    Think of this way... at what frequency will a RC or RL resonate?? That will lead you to your answer....
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    Whats a switching diode?

    There isn't anything very "special purpose" about switching diodes, as Audioguru points out in mentioning the 1N914 and 1N4148, which are quite common/generic. Semiconductors in general, that are used at microwave frequencies are COMPLETELY DIFFERNT ANIMALS.
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    Need help saturating a transistor for 2 amps

    Greetings John at this point voltage has nothing to do with it if the above condition is true. Beside, that "general rule" to which you refer, only applies to a "single" BJT.
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    The difference between using one 555 timer and a 556 timer for PWM control

    One thing that will happen when you use a single 555 as a PWM is that the switching frequency will move around (a lot) when you vary the voltage on the control voltage pin.
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    Need help saturating a transistor for 2 amps

    A transistors Vce sat voltage is current (Ib & Ic) dependent. For example, with Ic=10A & Ib=3.3A the 2N3055's Vce sat max voltage is 3V, while with a Ic=4A & Ib=400mA, the Vce sat max voltage is 1.1V A darlington transistor will saturate just like any other transistor. The only...
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    Free to try Sound Card Oscilloscope, Spectrum Analyzer and Signal Generator

    Yes, yes... at a minimum, you have to sample at least twice the frequency your trying to measure... blah, blah, blah. You could sample all day at 1000x the frequency, but unless you know where your starting from, it's worthless. It's still all based on some reference!!! It can only multiply of...
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    PROBLEms of LM317

    Yes you can, you have to "off-set" the adj pin lower resistor to -1.2V. Now... how you get the -1.2V is another story. The key is to be able to have the adj pin go to zero.
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    Free to try Sound Card Oscilloscope, Spectrum Analyzer and Signal Generator

    Of course there is error, the question is how much and does it matter... what's the accuracy of the reference clock?
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