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    weird behaviour from my amp circuite

    You wrote: Here is the schematic found on page 6. Where the power supply is, I added a label in green text. The voltage may not necessarily need to be 50V. There are many ground icons. I believe J1 at left is where the signal is supposed to be applied.
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    weird behaviour from my amp circuite

    1. When components burn it's pretty certain your circuit draws overmuch current from the power supply. 2. Your voltage varies because your circuit draws varying amounts of current at different frequencies. Your components create different impedance (that is, inductive or capacitive impedance)...
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    Amplitude modulation, lower carrier on max audio?

    At high volume the AM carrier needs to make larger excursions. However at low volume (or idle) there's the question, What is carrier intensity? 50 percent? 100 percent? Your experiment suggests it's more like 100 percent, even though it might seem wasteful to use full power broadcasting...
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    how do we choose the value of a dc block capacitor for an lna?

    The signal comes through a given series resistance (which may be unknown or unseen). Try to select a Farad value which produces an RC time constant covering 3 or 4 AC cycles. The capacitor charges to a DC voltage and should not vary more than 5 or 10 percent during a cycle, or whatever amount...
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    MRI RF enclosure/tent

    Many internet articles tell how to make a Faraday cage from a steel trash can with lid. Ground it to a wire embedded in soil. By putting radios, computers, medical devices, etc. inside it they're protected from EMP.
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    TV antenna impedance plotting...

    Seems like directionality is a more prominent factor, which determines voltage and current produced by the antenna at a given frequency. Impedance relates directly to voltage and current, or rather, the ratio of voltage to current. If there's any current flowing, then it implies a load is...
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    Microwave detection circuit verification

    A large assortment of simple rf detector circuits can be found via internet search. Many have a long antenna wire instead of the inductor used in your schematic.
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    Logic of coupling value in tandem 3dB connection

    Could this have to do with the principle that a series capacitor causes a phase shift of an incoming sinewave? At the frequency where 3dB attenuation occurs, the phase shift appears to be about 45 degrees, advance. However two parallel networks both advance the phase so net effect is zero, not...
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    Is feed through essential? and any idea about my design?

    Webpage with ampacity tables: https://amasci.com/tesla/wire1.txt It's too easy to yank on a wire connected to a pcb at a single spot. One twist or pull, and a copper trace can break away. However strength of the connection improves If you drill two holes and run the wire through both. Or...
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    Often it helps to vary supply voltage to an oscillator. There may be a certain range of operation such that transistor bias is the right amount, and sufficient swing, in order to draw necessary power from the supply, and feed it to the LC network, in order to maintain resonating oscillations.
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    Voltage and current profiles on patch antenna

    It might be easier to understand by going back to earlier days... When the antenna had twin-lead cable attached across a gap at midpoint. The antenna was 1/2 wavelength, yet separated into two halves. I guess it's to provide a node to tap for current (a power source, as it were) in order to...
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    Learning material for understanding how photodiodes work and how to use them

    I took an infrared photodiode and ground away the dark-colored plastic casing. I started to expose what looked like a small photovoltaic cell. Shiny blue brushed silicon appearance. About 1/8 inch square. A photodiode creates a voltage when light falls on it. Response is quick. The weak signal...
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    [SOLVED] Thompsonic radio - doesn't work

    Two wires are needed to carry power. Traditionally ground is black and supply is red.
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    Is there a simple way to make a NO dish antenna that can receive C-band or Ku-band satellite TV?

    Possibilities: * Can you place the dish indoors and point it through an open window at a transmitting satellite? * At reflected signal from a building or wall? * At the ground where a smooth surface reflects signal upward to your window? * Can you fabricate a smooth reflector which is a...
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    [SOLVED] Thompsonic radio - doesn't work

    It's important to determine if it's DC or AC? 1. If DC then it sounds as though the power supply board works. So if voltage doesn't reach the other boards, then you must find the faulty connection. The On-Off switch is one place to check. Soldered wires can break at the solder joint if flexed...
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    Simple transistor phase splitter (180 deg) for 1-30MHz?

    A transistor is a phase splitter in the sense you can take outputs from collector and emitter. Adjust values so as to obtain desired amplitudes. If desired change 0V ground to a negative supply voltage.
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    RF testing of three port device with two port VNA.

    Your situation sounds similar to the tv antenna cable formats... one old, one new. The old 300 ohm twin lead is differential. Later came 75 ohm coax which has the shield (ground) around a center wire (signal). A converter unit is recommended to go from one format to the other. Not sure if...
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    Designing differerntial Sigal modulator

    A half-bridge (as in your circuit) is useful when you want output that sinks and sources current (that is, switches between a low-ohm path to ground and to supply+). An alternative, if you wish to adapt class A transistor operation for your project...
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    Laser Measure Sensor (how to)

    The speed of light is so fast that components have a miniscule time to measure a reflected flash , especially at a range of a few inches. Or perhaps you're thinking of a geometric (triangulation) rangefinder? Did you see an article describing details of a laser rangefinder? Did you rule out...
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    HMC920 Active Bias Controller

    Perhaps this method might be adapted to your project. Biasing arrangement discourages thermal runaway (schematic I found in a book). If the transistor conducts too much, then the voltage at the collector goes down, automatically easing up on bias current, in turn reducing how much the...

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