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    Downconverter Mixer Design

    With that description one can only be designing a coherent demodulator. But in order to avoid the unusable output alluded to by davenn, synchronous AM demodulation requires the LO to be an exact duplicate of the carrier in both frequency and phase, which can at times be difficult to achieve...
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    basic of radio controlled devices

    In the USA frequencies for RC model operation are allocated by the FCC. See attachment. Most competition in the commercial market for RC transmitter/receivers seems to focus on direct sequence spread spectrum transmission in the 2.4 GHz band. I'm not aware of anyone making their own RC radio...
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    Nand Gate oscillator help

    I found the relevant schematic from the Higher Intelect Content Delivery Network. (Not sure if this is a legitimate operation, but it looks impressive.) http://cdn.preterhuman.net/texts/science_and_technology/other/Cutter%20-%20Electronic%20Circuits%20for%20the%20Evil%20Genius.pdf Note there...
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    Sinking and Sourcing Current Supplies?

    Current sources adjust their generated voltage to whatever is necessary to force the specified current to flow in the specified direction through the circuit. In this case both current sources generate e=7V. It would appear that both current sources were selected to be part of this problem...
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    How to setup KVL equations with element laws?

    I still remember when first learning circuit analysis that I would always use mesh analysis because dealing with loop currents seemed more intuitive than node voltages. But when I obtained Maple software for my Amiga computer to solve algebra problems it became most important to begin with a...
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    How to setup KVL equations with element laws?

    Then why is only one node equation necessary for a solution? Think about it.
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    How to setup KVL equations with element laws?

    Watching this exercise of trying to apply Kirchoff's Laws directly has been painful. Maybe I need some of those opiates, too. This circuit has one node plus ground so a single node equation is required. But I never fuss with writing down node currents since the purpose of KCL is to find...
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    Resistors in Parallel

    What if the computer recognized the parallel function ║; then you could write the answer as R+(R║2R)
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    When is 1 watt not 1 watt?

    It's not really a contradiction. With a complex series/parallel circuit where every component affects every other part of the circuit, it will be necessary to find the composite voltage or current of the entire circuit. This is done with simplification, alternately combining serial and...
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    When is 1 watt not 1 watt?

    Because even if the coursework did not ask both questions, the OP should be able to answer both questions, and explain the difference.
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    When is 1 watt not 1 watt?

    Both!
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    When is 1 watt not 1 watt?

    Did the course work ask the corresponding question: Given that each individual resistor can dissipate up to 1 watt of power before burning up, how much total power in watts ( W ) can the largest-valued composite resistor dissipate before burning up? What is the logic for finding that answer?
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    How to setup KVL equations with element laws?

    There is no reason to introduce i4 and i5. i4 is the same current as i1 and i5 is the same current as i2. How did you decide there is a 2V potential across R1? Let's start with your KCL node equation for A. It's OK although it violates my personal conventions but I'll try to work with it...
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    delay line memories and sram

    When Googling "delay line memory" you will be directed to places such as the Computer History Museum to see examples of delay lines using the technology of the 1940's. At that time SRAM was implemented with devices such as latching relays or electronic FF using vacuum tubes, whereas using...
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    mosfet basic calculations

    Idss is the saturation drain current with the gate shorted to the source (Vgs=0) so Idss is the maximum current possible.
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    mosfet basic calculations

    Vp is the pinch-off voltage, the gate reverse voltage sufficient to remove all free charge from the channel.
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    How to setup KVL equations with element laws?

    If you can identify the loops in a circuit, then you can write the loop equations. KVL applies to loops. If you can identify the nodes in a circuit, then you can write the node equations. KCL applies to nodes. So taking the example from above and explicitly showing what was implied for the...
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    mosfet basic calculations

    The interesting thing here is you don't actually need to know anything about FETs in order to solve the problem. But you do need to know which is the gate, drain, and source. You are given R1 & R2 voltage divider, 12 volts in, 4 volts out. You are given the parallel equivalent resistance of...
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    Flip flops

    Sun melts plastic. CDs are plastic.
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    Flip flops

    Consider what would cause a flip flop to lose its memory state. Would that then be permanent or temporary memory? Contrast that with another storage device such as a CD-ROM. Putting the CD in a parked car on the dashboard, at high noon when it is possible to fry eggs on the sidewalk here in...
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