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  1. (*steve*)

    Transformer power on both sides

    Google "power factor"
  2. (*steve*)

    How to draw this?

    I guess the answer is NO. Do you have a textbook?
  3. (*steve*)

    How to draw this?

    you need a protractor and a ruler. do you understand that one is an angle and a distance? Do you know how to plot that?
  4. (*steve*)

    Transformer power on both sides

    mathematically you can determine this, however if you have a definite phase relationship between voltage and current (the simplest is that they are in phase) then you can simply base your calculations on the RMS value of the AC voltage and the power factor. Which of these are you familiar with?
  5. (*steve*)

    Transformer power on both sides

    A current transformer requires an appropriate load. If it doesn't have one, the voltage is undefined. Typically this is a resistor of a certain value. This has the convenient effect of converting the current to a voltage for you. beware any thoughts that the current transformer doesn't load...
  6. (*steve*)

    LED strip power supply

    Often the fixed output power supplies have an adjustment to trim their output. If the one you get has this you may be able to reduce the output to maybe 11V. This doesn't sound like much, but it will reduce the current to the LEDs significantly. If not, it may be possible to modify the power...
  7. (*steve*)

    Thermostat with lm35: help finding out the error

    Remember that the LM393 has an open collector output. You will need to add a 2.2k resistor (or similar) from the output to the +ve supply to enable the output to go high.
  8. (*steve*)

    Modifying a spy microphone for leopard conservation

    how much mass can your leopard tolerate? This will determine the maximum mass of a battery. I guess the options are to transmit the audio or just record it. The latter simplifies some things, but you have to capture the animal twice. Are you planning to remove the collar or is it something...
  9. (*steve*)

    Heat sinking compounds

    evenly, but thin! The heat sink compound is not an especially good conductor of heat. But it's way better than air. You want the most metal to metal contact with the compound filling up the remaining air gaps.
  10. (*steve*)

    hello

    Hi Joe. Welcome to Electronics Point.
  11. (*steve*)

    Thermostat with lm35: help finding out the error

    can you post the schematic here? I can see it on dropbox but I can't zoom in on it to see what's going on.
  12. (*steve*)

    Mosfet heater control

    Damn, I'm sure I wrote a long and detailed response to this. Don't tell me I didn't hit "post" :-(
  13. (*steve*)

    How to find Area of Hysteresis?

    so now use the formula to calculate the area
  14. (*steve*)

    How to find Area of Hysteresis?

    Have you tried drawing a parallelogram which approximates the shape you have?
  15. (*steve*)

    How to find Area of Hysteresis?

    yes
  16. (*steve*)

    Book Reviews

    Off topic, but relevant. I've recently purchased books from a similar source. It pays to be very aware of the editions you're buying and to find reviews and read them. In some (rare) cases reviews actually praise earlier versions over later ones. In many cases the books get very poor reviews...
  17. (*steve*)

    PID for Kiln Control

    He needs to sun himself long enough to raise his body temperature above ambient air temperature.
  18. (*steve*)

    Transistor as switch with "Incandescent Lamp as load"

    You do it exactly the same way except you don't need a series resistor. Ensure that the circuit can cope with the low resistance of the bulb when the filament is cold.
  19. (*steve*)

    PID for Kiln Control

    Yeah, that looks reasonable. Several minor things: 1) I would put the fuse before the switch. 2) When you connect the thermocouple, to check you have it the right way around hold the thermocouple in your fingers. If the temperature shown increases you have it OK. If it decreases you have it...
  20. (*steve*)

    Mosfet heater control

    If you ramp the current up you may well evaporate the mosfet. If you want to be kinder to the heater (assuming it is running from AC) switch it on and off at a zero crossing of the mains.
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