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    Massive Heat Sink for MosFet ?

    eh, Sorry, like I said I slept through the (Heat Flows) part of the classes. (I lost it when we started talking about Resistance to Heat flow, I wondered if A high Heat flow through a High Heat flow resistance created something..? V = I * R  so  What = Heat *  Insulation.  All I could come up...
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    A "silly" question about a resistor and a led position

    ;D  am I?  ??? No. Just that the T&N theroms (When it comes to Resistor networks) are all about placement.  In a straight line Series circuit there is no difference. But in a mesh where the currents will be divided amoung different branches, the LED might not even light because the...
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    Stereo to Mono

    You guys had me worried for a while with all that talk about Post Amp signal Mixing. Whew. Yea, the Way it happens is all thanks to the Zenith/GE pilot tone multiplex system. But if that fancy widget fails, you can still get a mono signal.  The result is the combo of both left and right...
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    how do i interface a frequency counter with rs232

    Wow, now there is a doozer. Lets see. 1) Use a PIC that has the RS232 as part of the hardware.  Some chips have it built in. The PIC16,17 and 18 families are good places to start. The Smaller PIC 12 chips can also be used but you will need to download the RS-232 source code from MicroChips web...
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    A "silly" question about a resistor and a led position

    from one software person to another. Series = Single step modal program Parallel = Multi-step / Time slice / Non-Modal Program ;D To really start you off on the right foot. Resistors are additive.  If you need 10,000 ohms (10K) and you only have a box of 1000 ohm (1K) resistors. You could...
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    pnp vs npn?

    This only applies to PNP / NPN Bipolar transistors. (3906 & 3904 examples) A handy way to remember how they work is to remember what they look like inside. a PNP is made of 3 regions, Positive, Negative and Positive again. NPN is the same but reversed. In a diode there are only 2 regions...
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    Massive Heat Sink for MosFet ?

    Thermodynamics. Now there is a fun subject.  ::) Well I wish it was.  Having to build my first SUPER circuit I am having trouble handling the high current and temps created and I was wondering if anyone had a good solution for this type of challenge. The design is a H-Bridge that is rated at...
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    How does a 2-channel radio work?

    All correct: To expand.. In a 4 channel system, both the Tx and RX units are tuned to the same freq. AM/FM doesn't matter Just assume there is a wireless link between the two for now. Both units also expect to work with a fixed number of channels, in this case 4. The pulse train would run 4...
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    Why? Supply pins position differ in Dig & analog IC's

    The old Standard was to place the digital power pins in the corners of the chips. in the 70s this made board layout a bit easier.  Power buses ran between the chips in rows and they were much larger traces than the digital signals that could sneak in and out between the pins.  Analogue chips...
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    IGBT and MOSFET drivers???

    There are a few other clever parts to some driver chips. A few models supply a built in PWM generator. I like the HIP4080A for the projects I have worked on. It has a feed back loop analogue mode that generates the PWM onboard based on a voltage input target.  Although I have found that mode a...
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    IC problem

    When you say the port is on a PCB and connected to a 'Chip' Is this perhaps a UART or a Driver chip? For smaller projects I like the MAX232. I have had a lot of luck with an inexpensive logic probe. It shows 2 LEDs (Red=High, Green=Low) It is easy to follow a serial signal through a circuit...
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