Search results

Search Forums New Posts
  1. Alec_t

    Powering a linear actuator with a battery

    Welcome to EP! The battery should be suitable for infrequent use of the actuator. Since the actuator draws 3A, theoretically the battery would discharge completely in 2.3/3 hrs = 46 mins. However, it is bad for the battery to discharge it completely, so in practice a run time of 30 mins would be...
  2. Alec_t

    Pneumatic solenoid valve help

    Can you post a link to the valve datasheet? Edit: I would recommend building your circuit on Veroboard or similar, with soldered connections. Breadboards are not designed to carry heavy current (such as your solenoid may need) and do not provide reliable connections. If the connection to your...
  3. Alec_t

    Solenoid Motor Strength

    According to this chart I reckon the maximum current your coil can draw before it starts overheating is likely to be around 1A, in short bursts, since most of the wire will be buried inside the coil. If all 4 miles of wire is used to wind the coil in monofilar manner you would need a supply...
  4. Alec_t

    Parts needed?

    A strip of surgical tape over the affected area would protect it, and hopefully make him aware of his action each time.
  5. Alec_t

    Finding internal resistance of a cell/battery

    In the first pdf's circuit, is R supposed to be the battery's internal resistance or an external resistor? If the former, then the circuit is incorrectly drawn because R would have to be between the two terminals of the voltmeter. If the latter, then there are three resistance values to take...
  6. Alec_t

    Questions many hours for recharge battery lithium via USB cable connected in Hub USB

    I don't blame you :). I admire our stamina.
  7. Alec_t

    Questions many hours for recharge battery lithium via USB cable connected in Hub USB

    We have no idea what your hub characteristics are or what USB negotiations (if any) occur between your pen and the hub, so can't say if it's normal.
  8. Alec_t

    Astable 555 500Khz 20ms

    I only learned that today :).
  9. Alec_t

    Astable 555 500Khz 20ms

    Good question. 500kHz was an international distress frequency but is now in an allocated Amateur Radio frequency band, and driving the coil with a square wave is likely to result in a lot of unwanted RF interference from the harmonics too.
  10. Alec_t

    Double Potentiometer

    In principle, yes. The number of switch poles required would depend on how the original pot is wired.
  11. Alec_t

    Double Potentiometer

    Unless you have suitable measuring equipment and a schematic for the controller you will probably need to buy another one :(.
  12. Alec_t

    How can I make Audio Amplifier from 2SK3549-01 MOSFET

    BC856B is a pnp transistor, so won't work well as shown. A base resistor to limit current should be added.
  13. Alec_t

    How can I make Audio Amplifier from 2SK3549-01 MOSFET

    Rather than a single transistor (mosfet or bjt), have you considered an LM386-based amplifier (such as one of these) available cheaply ready built?
  14. Alec_t

    12 / 24 or 48v to 400V Boost Converter to charge electric car from solar panels

    What type of battery? Lead-acid, lithium, ......? Batteries generally need a type-dependent specific charging profile to charge them safely and efficiently. Just applying a fixed 400V to them is not ideal and could be dangerous.
  15. Alec_t

    How can I make Audio Amplifier from 2SK3549-01 MOSFET

    That particular mosfet is not a logic-level type and may need at least 5V gate drive to work satisfactorily.
  16. Alec_t

    Astable 555 500Khz 20ms

    According to its datasheet the LMC555 can generate up to 3MHz, but can source only 10mA and sink only 50mA, so would need a buffer on its output to drive the resonant circuit. I can't see anything in the datasheet of the common BJT version of the 555 to indicate that it could generate a...
  17. Alec_t

    Astable 555 500Khz 20ms

    Welcome to EP! 500kHz has a period of 2uS, not 20mS. So what do you want; 500kHz or 50Hz continuous, or 500kHz interrupted for 10mS every 20mS?
  18. Alec_t

    Fluctuating ADC Reading for 4-20mA Pressure transducer input?

    Are you using screened cable between the transducer and the Arduino?
  19. Alec_t

    Crosswalk project using 2 555 timers and can only be analog

    Is this a school/college project?
  20. Alec_t

    My new multimeter

    Nice find. A bit of delicate bending of the needle will soon fix that :D.
Top