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  1. K

    single phase controlled rectifier for DC motor

    If you are using DC then what is the phase for? Are you using pulse width modulation? You have to have two signals for phase. Does the motor have multiple windings? An SCR will require anode current interuption to turn it off. This can be easily accomplished if you are working with low voltage...
  2. K

    AM/FM Radio Tuning methods

    Whether you are manually tuning or calculating, doesn't it seem like this is the method which enables you to widdle down a design. You do one and then the other until you are satisfied with the results. I am sorry I can't recommend anything.
  3. K

    single phase controlled rectifier for DC motor

    Your motor will have DC voltage so what is the phase? Phase involves two signals. Are you creating a PWM circuit? Does your motor have multiple windings? An SCR will require a means to turn it off which means you will have to have the voltage required for anode current interuption. If you are...
  4. K

    Another 4watt Transmitter Question

    What the circuit does is it creates an oscillator and the mic input modulates it. The oscillator is the tricky part I feel. I have not built an oscillator so I don't know for sure. I think the components need to be accurate. I would suspect your coils and the transistor bias. Tell me when you...
  5. K

    lm337t

    I have to fix the kit I have. The regulator seems to give out under higher currents after a brief while. I replaced the positive variable voltage regulator with the lm317t. This was easy to configure because I had the diagram. The lm337t which is the negative variable voltage regulator does not...
  6. K

    College textbook question

    I = C dv/dt is the equation I use most often. I also use E = 1/2 CVsquared. So I = C * 1/RC = 1/10 = 100mA Now the current goes to zero, so you can increase it to 5RC and the current goes toward zero. Interesting enough is that dv/dt is a number that is associated with frequency when doing...
  7. K

    Problem w/ j/k flip flops?

    I would recommend using an integrated form of the counter. Using discretes is just a step in the wrong direction. However, discretes do work very good. The one thing I notice is that integrated circuits often come with things that are not wanted. But I think with any luck you could located a...
  8. K

    Problem w/ j/k flip flops?

    What kind of sequence are you trying to create?I don't see anything meaningful to the sequence. Although I looked at the site "How Stuff Works" and they had the same circuit. I don't see the sequence. It may be a repeatable sequence that has sixteen states but not incrementally. I would be...
  9. K

    C problem

    I need to know the process for serial communication under WindowsXP. I need to know what to include and what to load. I have the inpout/inpin files but I don't know if they are just for parallel port interfacing. Could somebody post the C code for please.
  10. K

    Latch triggering

    One is being powered by a battery, the other is not. But when I connect the battery I am connecting it to the power supply. I think this is a natural phenomenon.
  11. K

    Latch triggering

    I tried to start this oscillator by using a battery source. When I connected the battery, the oscillator seemed to be in phase with this other oscillator on the same circuit board. I don't know how exactly they were in phase, but it was close. Does this make much sense to anybody? The only way I...
  12. K

    C problem

    Here is the example I can't get to work. What could the problem be? rs232.txt
  13. K

    Latch triggering

    What determines the startup phase of an oscillator? I have the feeling that the startup is in phase with this other oscillator. Could it be that the oscillator startsup in phase with another oscillator just because they are in close proximity and have the same frequency?
  14. K

    pulse width modulation

    The circuit is correct. The problem is that the classic oscillator has a capacitor charge discharge to it. This makes the square wave not so square.
  15. K

    PSU repair, found strange cap, need guidance

    That is one strange device I must say. It would be interesting to see the circuit. One capacitor with four leads that go to wherever. It could be a parallel path. Have you thought of that? It's like the diode with three leads. They make them that way to realize a certain function. It is actually...
  16. K

    multiplexed led display prob

    If you want to incorporate transistors with logic functions then you need a series resistor and a parallel resistors combination. I normally disregard the sink and leave it open. The source current should fall within the recommendation. You can bias the parallel combination to give you...
  17. K

    PSU repair, found strange cap, need guidance

    I think a short is possible, but not on both sides as you have said. Maybe both sides have a connection to ground. Could you ground a can. Inspect the traces for ground connections.
  18. K

    Switch Transformer

    Hotwaterwizard, how do expect to get 220v from a 9v without a stepup transformer.
  19. K

    PSU repair, found strange cap, need guidance

    With shorted leads, aren't you shorting the two traces together. If they are supposed to be shorted, then why aren't they. They normally don't short two traces together using a component.
  20. K

    PSU repair, found strange cap, need guidance

    That looks like two capacitors rolled into one.
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