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  1. (*steve*)

    Heated Jacket not working

    Unless there is a charger circuit built into the jacket, that is not a suitable charger. Then the battery may be dead. Does the good battery gt warm when the jacket is turned on? You may have shorted the heating elements. Can you tell us exactly what the resistance of the heating element...
  2. (*steve*)

    Static Detector

    What is an FDS8589A? Can you point me at the datasheet you're working from?
  3. (*steve*)

    Can anyone recommend a simple linear VCO?

    yeah, sure. Give it a go. It essentially matches my suggestion of a constant current charge/discharge of a capacitor.
  4. (*steve*)

    Why is this LED not 20 Watts?

    Yes, but unless you measure the load voltage and current to determine what they are, a measurement of the mains is moot (assuming it's in spec -- 85 to 265V). If the change in mains voltage from 220 to 185 results in a change in the current from 600mA to 550mA, we know more by measuring the...
  5. (*steve*)

    Why is this LED not 20 Watts?

    The input voltage is not an issue. Measuring the LED voltage and current will tell us the story. Even if the input voltage causes the output current to vary, the measurements of the load will tell us.
  6. (*steve*)

    Sorry if I appear lazy....

    It may be useful to someone in the future who needs to do a similar thing.
  7. (*steve*)

    Can anyone recommend a simple linear VCO?

    The only thing I can think of is a constant current source controlled by the "linear" voltage. This could be used to charge a capacitor. If the discharge is sufficiently rapid, the frequency would be fairly linearly related to charge current. You would get a sawtooth or square wave output If...
  8. (*steve*)

    Can anyone recommend a simple linear VCO?

    The standard way of doing this is 1V per octave. Is that what you're doing? (you did mention linear -- I hope you really didn't mean that)
  9. (*steve*)

    Can anyone recommend a simple linear VCO?

    Is your plan to have each key on the keyboard produce a different voltage which of feed into a VCO to produce the appropriate note? If so, a better solution is to simply trim the voltage produced by each key to produce the correct frequency. However, if you're going to that effort I'd wonder...
  10. (*steve*)

    Which relay should I use?

    Google back emf. Google for the pros and cons of wye and delta. For a controller rated at X volts and Y amps, and having enough internal smarts to not exceed the current limit: It is current limited when supplying the full voltage it has available would cause the current limit to be exceeded...
  11. (*steve*)

    Why is this LED not 20 Watts?

    Yes, you ensure your load requires at least 32 volts to draw 600mA Can you measure the current drawn by your LED when connected to this driver and the voltage across it?
  12. (*steve*)

    Hello All

    Hi. How is the hobbyist electronics situation in Thailand? Are parts easy to get hold of? Welcome to Electronics Point.
  13. (*steve*)

    Why is this LED not 20 Watts?

    The issue might be that the LED is indeed a 20W LED, the driver is indeed a 20W driver, but the driver does not match the LED. That driver is a 600mA constant current driver. For a power of 20W, the LED voltage must be about 33V. If the Vf of the LED module is around 15V at 600mA, that would...
  14. (*steve*)

    Broken Project Kit Amp Circuit (Blown Capacitor) Repair tips

    That's a reasonable conclusion. If any resistors failed you would probably see some charring
  15. (*steve*)

    Broken Project Kit Amp Circuit (Blown Capacitor) Repair tips

    Did you connect the capacitor the wrong way, or the bridge rectifier. If the former, then maybe only the capacitor requires replacement. If the latter, you may well have destroyed semiconductors in the circuit.
  16. (*steve*)

    Which relay should I use?

    Delta gives double the torque, but requires 3 times the current. At low speeds when your controller is current limited, this will result in lower torque. At high speeds, when the controller is voltage limited (I.e. It cant supply enough voltage to reach its max current) delta allows a greater...
  17. (*steve*)

    IR tx & Rx

    And my comment on that would be: Purchase your electronics from someone you trust. If you don't trust them, don't buy from them. To that I add the caveat that if you personally know enough to be able to reliably test the parts you receive and are prepared to take the risk, you can purchase...
  18. (*steve*)

    Which relay should I use?

    It means that you are switching to the alternate configuration when the motor is already spinning at a relatively high RPM. That's nowhere near stalling.
  19. (*steve*)

    5-bit synchronous sequence recognizer design

    Your image is not visible. Upload it here, don't point at an image at another forum that presumably requires that you are logged in to view it.
  20. (*steve*)

    Which relay should I use?

    At higher speeds there is a higher back EMF from the motor. This effectively limits rpm to that where the back EMF balances the available applied voltage. If you reconfigure the motor so that the back EMF is lower then the same applied voltage will permit a higher rpm. Even though the stall...
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