Recent content by THRILLHO

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    Gate drivers for IGBT inverter: How to isolate V supplies?

    Thanks you two. I didn't know that all-in-one three phase gate drivers exist. Very convenient that they require only one power source. Saves me a lot of time, space, and money.
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    Gate drivers for IGBT inverter: How to isolate V supplies?

    This video describes my issue pretty well (I have it set to start when he talks about my specific situation): ETA: looks like the board doesn't allow the video to start at the specific time, the important stuff begins around 5:30 Our applications are a bit different as his design is for...
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    Using PLLs as FM Receivers: Why It Isn't Possible

    One last question, I promise. I can't for the life of me find the typical cutoff frequency of the LPF in the PLLs. Any idea? Thanks a lot for the help.
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    Using PLLs as FM Receivers: Why It Isn't Possible

    Will try tomorrow, thanks for the advice.
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    Using PLLs as FM Receivers: Why It Isn't Possible

    "How much deviation are you using with your modulation? ie what is the centre frequency and the lowest and highest frequency of your input carrier?" Saw "deviation" on the function generator and wasn't sure what it was. I know I played around with it and swung it slowly from around 2khz to...
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    Using PLLs as FM Receivers: Why It Isn't Possible

    http://www.most.gov.mm/techuni/media/EcE_02012_7.pdf Page 175 shows exactly what the DC level should look like. I can NOT get this kind of response. Again, on the o-scope and DMM, all I'm getting is a fairly steady DC level that only changes when I make major changes to the carrier. Any ideas?
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    Using PLLs as FM Receivers: Why It Isn't Possible

    Yeah, I'm frequency modulating the carrier. "Just from your figures, if you varied the carrier frequency from 9 KHz to 24 KHz the output would vary from 5.6 Volts to 3.5 volts. This is 2.1 volts of output from an FM signal." Which I am. But, again, that DC level is pretty steady, and in no...
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    Using PLLs as FM Receivers: Why It Isn't Possible

    I know it's not constant, but it's pretty steady on the O-scope. The DC level at pin 7 doesn't appear to be affected at all by the modulated frequency. It changes from 3.5 V near the upper lock frequency (about 24khz) and 5.6V around the lower lock frequency (about 9khz). But that is only done...
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    Using PLLs as FM Receivers: Why It Isn't Possible

    Yeah, I'm using a 565 (Motorola's). It's arranged pretty much identically to the schematic on the top left of page 87 of that PDF.
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    Using PLLs as FM Receivers: Why It Isn't Possible

    I'm having a lot of trouble understanding the demodulation aspect of the PLL. I understand FM modulation pretty well. I understand the three components of the PLL and how the react to each other. What I don't understand is how the supposed demodulated output of the PLL in any way resembles a...
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    Using PLLs as FM Receivers: Why It Isn't Possible

    Because I see FM radio kits all over the internet, and none consist of solely a PLL and antenna. Thanks. Why? This is the schematic for the transmitter I'm making: http://www.simplecircuitdiagram.com/2009/05/28/single-chip-fm-transmitter-for-short-range-application/ Says 88 to...
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    Using PLLs as FM Receivers: Why It Isn't Possible

    Because I see FM radio kits all over the internet, and none consist of solely a PLL and antenna. Thanks. Why? This is the schematic for the transmitter I'm making: http://www.simplecircuitdiagram.com/2009/05/28/single-chip-fm-transmitter-for-short-range-application/ Says 88 to...
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    Using PLLs as FM Receivers: Why It Isn't Possible

    I don't understand why a PLL alone can't be used as an FM receiver. I've got a project showing how PLLs are used and I'd like to use an FM transmitter (which I have a schematic for) transmitting wirelessly a signal that is demodulated by the PLL a few feet away. Seems pretty simple, where I set...