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  1. C

    Motors

    Servo motors are actually a box with a shaft at one end. The shaft connected to a gear box and the gearbox is connected to a 3-pole motor. You connect an arm (or lever) to the shaft. The arm then pushes or pulls to activate something via a rod. The arm does not rotate fully one complete...
  2. C

    Joining transformer wirer

    The only way is to bring it out as a tap, even if you are not going to use it as a tap. Obviously none of the others have ever wound a transformer.
  3. C

    12v Fan Reduce speed in every minute interval using 555 timer.

    I have explained how they work on my website and you would still not comprehend their operation. They are the most advanced DC motor. Their operation is brilliant and it is only through the advent of the HALL EFFECT device that they were able to work. Explain to me the simplest question...
  4. C

    12v Fan Reduce speed in every minute interval using 555 timer.

    He is possibly talking about the highly sophisticated brushless DC motor.
  5. C

    Turning supercapacitors into batteries

    Do you realise how many farads a simple 3.7v 18650 cell is?
  6. C

    parallel led array

    Basically you cannot drive high power LEDs from a 3.7v battery and include a diode and current-limiting resistor. You do not have enough head-room - any ghost buster will tell you that.
  7. C

    12v Fan Reduce speed in every minute interval using 555 timer.

    Your requirement is very complex and beyond a beginner.
  8. C

    Getting a led to turn on when voltage is under 3 volts on a battery

    This circuit flashes when the voltage drops to 4v. The voltage "set-point" can be adjusted by changing the 150k on the base of the first transistor.
  9. C

    Changeover Switch Relay?

    You just need a flip flop and a relay. But you need to start with a circuit and then work on improving the circuit until it is correct. You need the circuit powered all the time and the logic (the commands) comes from the timer to turn the motor ON and OFF.
  10. C

    Burnt out Blanket Controller

    The quickest and easiest way to fix the board is to remove the black things you can see in the photo above and measure between each and ever one of the pins with a multimeter set to LOW ohms. If the needle moves right across the scale when the probes are in one position and also when they are...
  11. C

    Low Cost PCB Manufacturers

    All "Free PCB design packages" offered by PCB manufacturers are a TRAP. You cannot get your design without paying a fortune and they charge an ENORMOUS amount to make a few PCB's. Use free software and get a manufacturer like Elecrow http://www.elecrow.com/ to make the boards.
  12. C

    Homebuilt Signal Generator

    If you want a known, fixed frequency, you can use a microcontroller.
  13. C

    Homebuilt Signal Generator

    If you build a square-wave signal generator you can use its harmonics.
  14. C

    DC motors

    You can only make a brush-type motor. If it has 2 poles it is not self-starting. If it has 3 poles, it is self-starting. The secret is the commutator - the thing at the end of the armature where the brushes touch little pieces of copper. You have to look on the web to see how to wind the...
  15. C

    2-stage Class A Amplifier: Gains(voltage and power)

    You have to start by drawing the circuit and showing the load and if the two stages are directly coupled or capacitor coupled.
  16. C

    2-stage Class A Amplifier: Gains(voltage and power)

    You don't want each stage to be more than about 50, otherwise you will get a lot of instability - called "motorboating." When we talk about a "gain of 50" we mean voltage gain for the first stage - called the pre-amplifier stage and a "gain of 50" - meaning a current gain for the output stage.
  17. C

    Arcs from Van de Graaff Generators and Tesla Coils

    You can look all this up on the internet. It all has to do with IONISATION of the air.
  18. C

    What function do these coil

    To start with, there is nothing you can do with the "coils." Reading a resistance-value tells you nothing. The only thing you can do is determine of the coil is an inductor or transformer. If it has two terminals, it is an inductor. If it has 3 or more terminals, it is a transformer.
  19. C

    Arcs from Van de Graaff Generators and Tesla Coils

    The distance is also due to the frequency of the voltage.
  20. C

    Microcontroller LiPo Charger

    Creating a battery charger is way beyond your capabilities. You can buy single cell INTELLIGENT chargers on eBay for $2.00 These have taken hundreds of hours of design-work to develop, and you think you can put one together in an afternoon.
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