Recent content by rp55

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    How does this circuit *really* work: 2 transistor metronome

    So perhaps you're saying that since R1 and C1 are in parallel now, and so both parallel branches should see the same voltage which would be per led's limiting drop of 1.5v (or whatever we said)? So they both get different current but the same voltage since they're parallel? Why does the led get...
  2. R

    How does this circuit *really* work: 2 transistor metronome

    Doesn't there have to be a voltage drop (even if in opposite direction) on R1? That's what I was calculating in. But I definitely missed C1 discharging thru R1 the way you show. Good stuff. I've learned a lot.
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    How does this circuit *really* work: 2 transistor metronome

    Right... 1/2 second in this case. So instead of time constant formula R*C (63% charge) you use 5 for full charge? Is that what you did there? I didn't know that, very useful. Oh I didn't realize this. This is very useful... since you can't give the cap a resistive value. Then you can use ohm's...
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    How does this circuit *really* work: 2 transistor metronome

    Right. I was confused about how capacitor works. They oppose a CHANGE in voltage, not oppose voltage the more they get charged (that's what I was thinking). Thanks for pointing that out! That should help me to understand better as that was throwing me off (and why you didn't understand what I...
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    How does this circuit *really* work: 2 transistor metronome

    Jony130, I believe you are saying there is a discharge and that state F does occur when you said: C1 right plate ---> speaker---> power supply ----> R1 + R1---> C1 "left" plate. So it sounds like I'm on track there. It will help if I go over your numbers I'm sure I'll learn more from that...
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    How does this circuit *really* work: 2 transistor metronome

    Thanks for that Jony130! I'm still working thru your last part and trying to understand the actual numbers. But I wanted to present things in a way I can understand a bit better via some the various states being presented in a way I currently understand. Perhaps you can pinpoint where I'm going...
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    How does this circuit *really* work: 2 transistor metronome

    Well I thought I understood this circuit and posted a big explanation of how I understood it but now I'm stll unsure... what a mind screw this thing is.
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    How does this circuit *really* work: 2 transistor metronome

    Thanks for the response Jony130! Right, got it. Oh I see. I think I was missing that. I understood Q2 was in saturation region, but it didn't dawn on me that since it was pretty much a closed circuit thru Q2 ce (limited only by the "saturated" --wrong term likely-- inductor coil) so this...
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    How does this circuit *really* work: 2 transistor metronome

    Ok so I think I've just about got this figured out (as much as my brain can take) given all the help from this threads responses and the other thread posted by Jony130 and the info over at the talkingelectronics site. So to beat this dead horse once again! Basically, the cap is getting charged...
  10. R

    Machine Design - How To Determine Motor HP Etc.

    So how many watts to get it up to speed (1 meter per second) for one second?
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    Machine Design - How To Determine Motor HP Etc.

    Thanks for the constructive criticism. So I'm curious then since you seem to be in the know: how many watts would it take to pull that 1500lb load for 1 meter in 1 second with no slope?
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    How does this circuit *really* work: 2 transistor metronome

    Thanks so much! I can't wait to sit down and go through those!
  13. R

    Best programming language for a microcontroller?

    Absolutely your comment is 100% valid, sorry if it came off as a negation. I agree he needs to understand architecturally what entails both IC types before proceeding (of which a bios is a key part of). I guess the reciprocal might have been if we said he needed to understand chip programmers...
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    Best programming language for a microcontroller?

    I know what you're saying but a microcontroller doesn't require a "BIOS". A microprocessor does. He seems to be leaning towards microcontrollers more. A microprocessor (more difficult to deal with from scratch) has no storage for a program. A microcontroller does and can be flashed or...
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    Machine Design - How To Determine Motor HP Etc.

    Newbie here but I'll give you my 2cents: I would assume do calcs without grade first for simplification: 1 Horsepower is equal to the force needed to move 550lbs 1 meter in one second. So you would need about 2.7 horsepower to move that load (no slope) 1 meter per second (assuming no...
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