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    Using 2N3904 for 3V audio preamp

    Thanks everyone for your input. I went with the FET approach
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    What integrated circuits, etc. for an amateur?

    Hi I cannot define exact parts because that is project specific . I can help you with a partial list of parts that I use. I work mostly in the 3.3 to 12 volt range in my projects. Metal film resistors Various types of capacitors Lm339 quad comparator Lm324, lm358 op amp Ln380 audio power amp...
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    Using 2N3904 for 3V audio preamp

    Thanks for you help. I found a CD4069 hex inverter in my supply of parts, and a n channel JFET. I think I will take your advice and try many different configurations that have shown me. I majored in electronics (B.S.) a long time ago and have become interested in circuit design and it's...
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    Using 2N3904 for 3V audio preamp

    Thanks everyone for your help. I am sure if I replied properly to Svein, but it looks like there is the usual voltage divider bias circuit consisting of Q1 with the addition of Q2. It looks like Q2 is being used as time varying current valve. When the collector voltage at Q1 is lower than the...
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    Using 2N3904 for 3V audio preamp

    I want to use a 3.3 volt supply to power a voltage divider biased pre-amplifier using a 2N3904. My input signal level is 50mv p-p with a 50 ohm source resistance. I am looking for a gain of about 50. After doing the math and building the circuit, my design works, but in order to get a...
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    What's in an electronics hobbyist's toolbox?

    Thanks Jim and usablethough for your input
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    Need help with my project -- microcontroller for DC motor controller

    Here's a suggestion that might help. Since the micro controller will need drive circuitry to control the DC motor, try to design and test the drive circuit as a stand alone project with the input requirements of the driver corresponding to the outputs from the PIC Micro controller. If your...
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    What's in an electronics hobbyist's toolbox?

    Thanks Jim, I have a ground system that I bought that has a 1 Mega ohm resistor in the wire from my wrist strap to a eyelet on my mat. From that point it is connected to earth ground via a receptacle. The 1 Mega ohm resistor should safely limit the current to 2ma or so if a 2Kv potential was...
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    What's in an electronics hobbyist's toolbox?

    I use a ESD mat and grounded wrist clip when working with more static sensitive parts including the assembly of circuit board based prototypes.
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    Voltage between two points on an empty wire

    how does the comment relate to my last post? There seems to be a disconnect somewhere. Do i need to avoid the "keep it simple" ? it seems like deep theory wasn't going to answer the question.
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    Voltage between two points on an empty wire

    Being new to these posts, perhaps another way to help answer this question is ask what is the voltage across the lamp versus the voltage across the battery? They should be pretty close to the same (ideal case- no IR drop in wire for a given distance ). Per the drawing, because the voltage...
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    Voltage between two points on an empty wire

    Keeping things simple, the resistance of the wire between points 1,2 or 3,4 is zero (in the ideal case) volts because the resistance is very small very small. The resistance will depending on the IR drop of the wire between those pairs of points. The farther apart they are, the greater the IR...
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