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  1. duke37

    Woo-Woo Power saving speculation

    By studying physics I meant learn about volts, amps, watts, resistance, frequency, inductance, capacitance. When you know what these mean, you can get your mind boggled with thermodynamics and entropy! I used to use an electron microscope, it had a lot of very energetic electrons but I never...
  2. duke37

    Relay or contactor for 50KHz, 1.9Arms?

    You still do not mean 50KHz, you mean 50kHz. The contactor referred to is 5 pole. Putting all 5 contacts in series will enhance the voltage capability.
  3. duke37

    how often..

    The audio amplifier will have been designed by people who know what they are doing. The design will be a compromise between complexity (cost), power output and distortion. If you wish to do cheaper and better then you will have to do a lot of learning.
  4. duke37

    Woo-Woo Power saving speculation

    Changing the voltage will not affect the power required to drive a microwave or oven. Dropping from 240V to 12V means that you will need different circuitry and cables 20 times as thick. Home produced power is expensive, if you wish to save, then get the house insulated properly. I think...
  5. duke37

    Relay with 50KHz, 1.9A rms?

    You mean kHz not KHz ! The relay should stand the current but you do not say what voltage it is switching.
  6. duke37

    Need help

    If you go the switch route to energise the solenoids, put the supply on the common terminal. Using Harald's table, connect the outputs as follows. gear 1 connect to A gear 2 no connection gear 3 connect to B gear 4 connect to two diodes, one going to A, the other to B. The diodes are...
  7. duke37

    Converting PWM output into a voltage using low pass filter.

    The nomal way is to use an inductor. These can be seen in computer power supplies, they are wound on ferrite torroids. the wire should be thick enough to take the maximum average current, the starting current should not be a problem unless the motor is reluctant to start. A diode from ground...
  8. duke37

    Couple of Questions On Filters

    A pendulum on a clock runs at a resonant frequency. At the one extremety, the pendulum weight will be slightly hgher and so will have potential energy. As the pendulum swings across it will have kinetic energy. There will be an interchange of potential and kinetic energy until resistance stops...
  9. duke37

    Need help

    This can be done with a four position switch and some diodes. You will need a mechanical arrangement to move the switch one way when one paddle is pressed and it should be moved the other way when the other paddle is pressed. This would eliminate electronics at the expense of mechanical...
  10. duke37

    resistor question?

    There are several places to get components in the UK. I get my bits from R.F Potts of Derby. Most big towns have a Maplins. RS components, Farnell, Cricklewood, Bowood are alternatives to get them by post.
  11. duke37

    Looking for an on/off digital toggle signal chip

    The CMOS 4066 is a quad analog switch. It will only take signals so if you want to pass power, you will need something better.
  12. duke37

    Comparator for anemometer

    The 5532 needs a minimum of +/- 3V supply i.e. 6V with the inputs somewhere near the middle. It has a long tailed pair input which will need to be a volt or two above the negative supply. Pin 8 is the positive supply and is normally shown at the top of the diagram. You show a negative supply...
  13. duke37

    Comparator for anemometer

    The TL081 needs a minimum of 5V supply. See TI data sheet. It is best to have the positive at the top of the diagram and the common connection below. Have you got the power connected properly, you do not give details of the TL081 pins. R3 does nothing other than reduce the output...
  14. duke37

    pass transistor

    Wikipedia gives information on a pass transistor. The material they are made of is normally doped silicon.
  15. duke37

    AM Detector simulation problem

    The active rectifier circuit looks correct. The waveforms are a bit fuzzy, perhaps the time steps are too high. The diode output is connected to the circuit output so the waveforms will be the same.
  16. duke37

    Please help understand this circuit .

    Has the big fat capacitor got a domed top? What is its capacitance and voltage?
  17. duke37

    De-soldering wick, pump, or gun type?

    I have used the braid from coax cable as solder wick, it might need a little flux. If the cable is too old, it will not tin easily.
  18. duke37

    Can oscilloscope somehow be used as curve tracer?

    I have a scope but rarely use it and have never made a curve tracer. The scope has an amplifier which alters the height of the spot (Y deflection) The scope has a timebase which moves the spot across the screen (X deflection). To curve trace these two must be correlated. Some scopes...
  19. duke37

    Not Working on Proteus ISIS

    Perhaps the aerial is not picking up sufficient signal. Seriously, the motor power and type of motor is needed. What is the power supply. The IC contains a triac which indicates it might be an AC supply driving an AC motor. The led will not like this at all. Someone may be able to help...
  20. duke37

    Laptop DC Adapter - Burnt Out

    Ey oop I have had another look at your pictures and the transformer is not a normal mains to low voltage transformer with a laminated silicon steel core. There is a 400V 120uF capacitor which indicates that it is a switched mode supply. The mains is rectified (240V * 1.414) to give about...
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