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  1. WHONOES

    Unknown soldering device needed

    What you need is some PCB Terminal pins made by Vero. They push fit into the board from the copper side and are very cheap and extremely versatile. Try googling Vero 18-1658.
  2. WHONOES

    14.4 V Lithium battery - re-purposing question

    17V is just a tad high. 4.2V per cell is the norm. You will also have to limit the charge current according to what ever is says on the battery pack. When a battery is fully discharged (in the case of your LiPo it will be 12V) a substantial amount of current can be drawn due to the difference in...
  3. WHONOES

    Grounding Question

    Having had a quick look at the device, it looks as though you just connect it across the speaker leads.
  4. WHONOES

    Resistor Value.

    The gold band indicates a multiplier of 0.1. Green = 5, brown = 1 so, your resistor should be 0R51. The brown band is for tolerance of 1%. Edit: forgot the black band. Doesn't change the value though.
  5. WHONOES

    Help needed with project

    Look up ASCII coding.
  6. WHONOES

    Resistor

    Nichrome works but, it would need to be on a heatsink of some sort or else its resistance will increase with temperature. The best solution would be for a thin film high wattage resistor on a heatsink.
  7. WHONOES

    Resistor

    Yup, it could have a highish impedance if the current is ac.
  8. WHONOES

    Resistor

    Most likely, which is why it's not practical. It would make a fairly large coil with a fair amount of inductance.
  9. WHONOES

    Resistor

    Don't like the copper wire solution. The 26AWG wire suggested is way too thin and would get hot when passing 8A especially if wound into a coil. If you were determined to use copper wire I would advise at least a 1mm cross section which equates to about 17AWG. Don't forget that as the wire warms...
  10. WHONOES

    Hello, can somebody help me with an240P

    I think you will have trouble building a receiver if you are doing it on a prototyping board. Too many stray fields and capacitance.
  11. WHONOES

    Help with MOSFET motor control

    Q2 could be getting warm because it is partially switched on courtesy of the difference between the 2 supplies.
  12. WHONOES

    Switches

    Makes sense.
  13. WHONOES

    Pressure sensor technique

    Strain gauges come to mind.
  14. WHONOES

    Help with MOSFET motor control

    I agree with you though I doubt if there will be any PWM effect as Q2 will be hard on whilst the drain of Q2 will be high impedance meaning there is no current path at all for the source of Q1.
  15. WHONOES

    Help with MOSFET motor control

    For the motor to run, Q3 needs to be switched hard on otherwise there is no current path to ground for the source of Q1. With Q3 turned on, the source of Q1 is pulled up to the + supply effectively shunting the motor. I think the notation of input signal Start barred is incorrect as that point...
  16. WHONOES

    DC 12-36V Lathe Press 555 Motor, Torque vs speed

    Applying more volts to the motor means it will demand more power (amps). It is roughly a square law where doubling the voltage means the motor will demand 4 times the current. If your power supply can't deliver the extra current required, the power supply volts will collapse to a point where the...
  17. WHONOES

    DC 12-36V Lathe Press 555 Motor, Torque vs speed

    Current consumption will of course vary with load.
  18. WHONOES

    Op amp problem ua741

    The inputs of the CA3140 I mentioned are guaranteed to 0.5V below ground if I remember correctly.
  19. WHONOES

    Technics SA-CH550 panel very dim, is it fatal

    Turn the lights out?
  20. WHONOES

    Replacing thermostat in a fog machine

    Have a look on the Farnell Lithuania web site. They may have something though I haven't looked myself.
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