Recent content by VinnyCee

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    Using a transistor as a (relatively) high speed switch

    Clarification: I am really looking for a part, in production, that can respond to the input pulse consistently. I've seen some datasheets (for example, this one) list the turn on time as 9ns typical to 12ns maximum and a turn off time as 13ns typical to 18ns maximum. I would want the...
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    Using a transistor as a (relatively) high speed switch

    I need a low cost method of switching, and the transistor is the lowest cost device I think. A logic gate would be a lot more expensive right? I am charging a capacitor and then using the switch to dissipate the charge from the capacitor into another, unknown, resistance and capacitance. And...
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    Using a transistor as a (relatively) high speed switch

    So I'd like to pulse a current to a load from a transistor. I can use a µ-controller to trigger a transistor. The µ only has a minimum pulse length of about 100ns or greater. But I would like to have the current flow through the transistor for a much shorter pulse length than 100ns. Maybe a...
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    Graduate Relationship between B and H fields in cylindrical magnetization

    So I've been simulating a really simple geometry using ANSYS Maxwell. It is a cylinder only and I am looking at the \overrightarrow{B} and \overrightarrow{H} fields in order to see their relationship between them when the material is magnetized in the circumferential direction. I used a...
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    When is a magnetic core considered saturated ? At 50% of core - 100%?

    What about for rods as like above?
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    Signs of the trigonometric functions of the angle -200

    http://planetmath.org/DeterminingSignsOfTrigonometricFunctions.html Since -200° lies in the second quadrant, then all are positive except for SIN and CSC, as described in the link above. Use the mnemonic device "All Students Take Calculus" as suggested and you will get any question relating to...
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    Values of the six Trigonometric Functions

    First, the questions states that the point in question is P(-3, 0) only? So we are to assume that the origin is the starting point? But if that is the case, then all we have is a straight line down the negative x-axis. This would imply that the angle measured from the positive x-axis is simply...
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    When is a magnetic core considered saturated ? At 50% of core - 100%?

    When is a magnetic core considered "saturated"? At 50% of core - 100%? So I am doing some simulations of inductors on the Ansys Maxwell software for electromagnetic simulation. I have a simple inductor with a Metglas core and copper coil. I'm trying to figure out what current is required to...
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    Linear movement detector using magnetic, wire coil and transistors

    I, too, am looking into building a device of this nature. I simulated the field of the magnet that I am required to use. When the NdFeB magnet is directly over a proposed sensor, it has a B-field of about 10 mT and a density (H-field) of about 8.5 \frac{kA}{m}. But it also has a B-field of...
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    Best material for a phone case?

    Carbon nanotubes are quite strong. It would be easier to brainstorm if you quatifid some of your requirements, such as Young's modulus, tensile strength, etc.
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    Undergrad Magnetic Sensor Sensitivity units mV/V/gauss, etc.

    I sent an email to a few manufacturers to inquire about what products they may have which would be applicable here. Hopefully they'll get back to me soon with some good news! It's not for a lab project, I'm trying to use it to make a device. Using the info in the OP, can anyone tell me what I...
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    Undergrad Magnetic Sensor Sensitivity units mV/V/gauss, etc.

    So let's say for the http://www51.honeywell.com/aero/common/documents/myaerospacecatalog-documents/Missiles-Munitions/HMC_1001-1002-1021-1022_Data_Sheet.pdf, which has a sensitivity of 1.0 mV/V/gauss, this would mean that for every 1 gauss change in detected magnetic field, there would be a 1 mV...
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    Undergrad Magnetic Sensor Sensitivity units mV/V/gauss, etc.

    So I've been looking at magnetic sensor datasheets and I see the sensitivity is usually listed in units of mV/V/gauss. What does this mean? Let's say I need to sense changes in a magnetic field that usually ranges from about 10 gauss ( 1 mT ) to about 130 gauss ( 13 mT ). And I need to be able...
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    Optimization problem solved two ways (algebra or calculus)

    Homework Statement A life guard sitting on a beach at point A needs to get to point B (Hasselhoff fell out his inflatable rocking chair) as soon as possible. The lifeguard (Pamela Anderson) can run (on the shore in slow-motion, like in Baywatch) at a rate of 3 m/s and can swim at a rate of 1.5...
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    Is there a way to prevent T1 stress tests from keying all radios at once?

    What is radio keying? So you need a filter that takes an RJ-45 copper input and outputs the same? That filter needs to filter out only properly framed T1 with all highs? Can you provide some more information about this T1 "high" signal?