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  1. L

    Need help with Judge Dredd Lawgiver LED lighting

    This could be done with something like the SN74HC174 Hex D-Type Flip-Flop w/ Clear and a 555 for clock generation. Connect the flip-flops as in a shift register and use the Q outputs to drive a transistor switch for each LED. The blue&red activation LED's could be driven by 1Q, with 1Q...
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    Oscillator Query

    A Bode plot of the Colpitts feedback circuit is attached. Representative component values were chosen for LC tank resonance near 50 KHz, mainly to investigate the phase shift behavior. Note that at resonance the circuit becomes simply a resistor divider for magnitude but with -180 degree phase...
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    Oscillator Query

    Phase shift of the LC tank circuit can be extreme near resonance. Search for "colpitts oscillator phase shift" will yield web pages such as: http://www.electronics-tutorials.ws/oscillator/colpitts.html http://hyperphysics.phy-astr.gsu.edu/hbase/electronic/posfe.html
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    Have a amazing idea and need a little help!!

    Since a battery will hold a hundred times more charge than a super-capacitor, I don't see the advantage of that approach over just charging a second battery.
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    Peltier tiles

    The ice cube is relevant because of your intent to be in winter weather wearing not an insulating coat designed to keep you warm but a Seebeck device designed to transfer heat from your skin to the cold heatsink of winter air. Now two square inches is probably not enough to give you frostbite...
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    Running a 6V DC Motor on 0-30V variable supply?

    Shall we assume that the motor is a permanent magnet motor with commutator brushes rather than something exotic like a brushless DC motor? If that is the case then one thing to realize is that the motor is also a generator. Attach a voltmeter to the motor terminals and manually turn the shaft...
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    Peltier tiles

    If you put an ice cube on a patch of your skin, how long will your patch of skin maintain a temperature of 98 F?
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    Seven segment display decoding

    I prefer doing the K-maps using positive logic, then making the switch to negative logic when selecting the NAND & NOR gates to use. It's less confusing that way.
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    Seven segment display decoding

    Here is what I would try for minimization. For display of the numbers 1-6 the values of 0 & 7 become don't-care conditions.
  10. L

    Two commutation processes for RL circuit

    It appears to me that the answer obtained by inspection agrees with the answer derived from the differential equation.
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    Seven segment display decoding

    So what does your truth table and Karnaugh map look like for each segment?
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    Equation to figure out the resistance to charge capacitors evenly

    The given reference speaks of leakage resistance on the order of 100 million megohms. Capacitor leakage/soakage is normally a concern in sample & hold applications using plastic film capacitors. Even so, leakage is not a concern during the charge cycle. If electrolytic capacitor leakage is a...
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    QAM Demodulation?

    Here is an idea of what is involved in QAM demodulation (www.wirelesscommunication.nl/pdfandps/qam.pdf). As for explaining how to do it, I would recommend buying a QAM demod chip.
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    Equation to figure out the resistance to charge capacitors evenly

    Depends on what you mean by 'to charge evenly'. Any network of capacitors (whether in series, parallel, or a hybrid of both) can be reduced to a single equivalent capacitance that will charge evenly. Capacitors in parallel will always be charged to the same voltage. Capacitors in series will...
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    Reduce transducer power for ultrasonic bath?

    Whether a wirewound pot would work depends on the type of oscillator and transducer used. If it is a ceramic crystal transducer and resonant oscillator circuit that depends on the phase shift of the crystal at resonance, then introducing a wirewound resistance in series with the crystal may...
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    help with circuit

    What is R2 connected to? And for what purpose? What does the piezo trigger waveform look like?
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    Value of RF (feedback resistor formula)

    Instead of trying to find the correct formula, why not derive it yourself? Just realize two facts: 1. When the 1 Vp-p input is at +1V the 10 Vp-p output is at -10V. 2. The '-' input to the opamp is a virtual ground. The '+' is tied to real ground and negative feedback keeps the '-' input...
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    Two commutation processes for RL circuit

    Yes, an open switch in a series circuit effectively removes the components that are part of the open circuit, while a closed switch in a parallel circuit effectively removes the components that have been shorted.
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    Removing a passive crossover from an amp

    It sounds as though you have an active crossover with near unity gain. So why would an attenuator need to be substituted for the crossover? Also, shouldn't a crossover have more outputs than it has inputs? I did not get that from reading your description. A schematic would go a long way...
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    Planet Monitoring Using Sensors - Senior Design Project

    Have you conducted an engineering survey to determine what necessary technology and components are commercially available versus what you might need to develop, and the associated costs? Have you conducted a customer survey to determine who might be interested in subscribing to your planet...
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