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    Redesign Elektor gigant2000 Amplifier

    He talkes about a biased Class-B but says this is not a Class-AB. The distortion caused by gain-doubling in Class-AB seems to be more of a problem to him than to deal with the crossover distortion in Class-B amplifiers. He also states that most amplifier designs suffer from so much distortion in...
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    Questions in Radio receivers?????

    a) C1 helps to improve the impedance match to the tuned circuit. b) Antennas of a certain length have a typical impedance at a certain frequency. The explanation given by the writer is too simplistic. It is a bit more complicated than that. I suggest you read up on type of antennas, impedance...
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    Redesign Elektor gigant2000 Amplifier

    I don't think "Self" is calling it Class-B by mistake as he states in the foreword of his book The problem comes that most people see a biased Class-B amplifier and think it is a Class-AB. "Self" sees the same amplifier from his Engineering analysis as a Class-B. Also from the book:
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    Questions in Radio receivers?????

    I once used this loading effect to design a switchable narrow-wide FM detector in a measuring instrument.
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    crystal oscillator transmitter

    Fundamental mode crystals can typically be pulled by 0.2% and overtone crystals much less than that.
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    Redesign Elektor gigant2000 Amplifier

    This is technically not correct. Reference: Douglas Self - Audio Power Amplifier Design Handbook, 3rd edition
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    Questions in Radio receivers?????

    Last diagram
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    Questions in Radio receivers?????

    1) Are u mean the series impedance of the antenna? And if so, What can the antenna be considered from this point? The capacitor add resistance in series so that the low characteristic impedance of the antenna (300, 75 or 50 Ohm) does not load the tuned circuit too much. (This will become more...
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    Questions in Radio receivers?????

    Receiver input design is a balance between losses and selectivity in the tuned circuit. More selectivity requires less loading of the tuned circuit. Less loading results in more signal loss, from the signal coupled to the tuned circuit. Connecting the antenna directly will be like connecting a...
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    A\D converters (sampling\oversampling)

    Theory tells us that to reproduce a signal waveform we have to sample at least  2X the bandwidth of the signal we want to capture. In practice we need more for accurate reproduction. For instance in digital oscilloscopes the sample ratio may be from 2.5 to 4+ You pay a price for faster sampling...
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    need a program to simulate in electronics

    I am not an expert with this program as I hardly ever use it. I find the user interface too clumsy and drawing large schematics a pain. There should be some option to display the node numbers on the diagram. You can go "view spice netlist" as another option. The dots indicate the phasing of the...
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    need a program to simulate in electronics

    If you wanted the circuits to be isolated, you may do something like this. Spice needs to see some path to circuit GND otherwise you will get an error. You may make the resistor much higher in value.
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    need a program to simulate in electronics

    Hope this helps. * L1 N003 0 1mH V1 N003 0 SINE(0 100 1000) AC 10 0 Rser=10 L2 N001 0 100
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    AM reciever mixer

    Here is osc startup with SWcad. Probe at emitter. Also current into emitter and in collector circuit
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    need a program to simulate in electronics

    In help files of SWcad
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    AM reciever mixer

    The program is not free. They used to have a student or demo version. I am not sure if that is still the case. This link http://www.campustech.com/c/campust/title.html?id=gDHxDQRf&mv_arg=NINT100&mv_pc=65 you can buy it for$35 You should be able to use Linear's switchercad also which...
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    AM reciever mixer

    Program is Multisim from National Instruments. I indicated a total phase-shift of 360 degee which bring you back to 0 degree, correct. In oscillator design the term loop-gain is used to indicate the total gain in the loop (gain of amplfier - any losses from tuned circuit and other elements)...
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    AM reciever mixer

    With all basic elements connected we can see that circuit starts to oscillate when power is applied.
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    AM reciever mixer

    It is important to note what happens to phase at the point of resonance. Look at the attached picture  of gain(blue) vs. phase(red) and it will become clear. There is no active gain due to absence of the amplifier. Now if you add the amplifier, the additional phase shift will result in a total...
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    School Project for "Electronics"

    http://www.electronicsforu.com/EFYLinux/circuit/may2003/ci4-clap.pdf
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