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  1. B

    Arduino Help... Error : "The programmer is not responding"

    I think you've answered your own question.
  2. B

    Best cheap material for diy low power heating element

    Perhaps you also should read Hevans1944 post above #6 and follow his links. He has good info there for beginners. To add to the sources of heating at low voltages one can also look at automotive bulbs.
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    Need help identifying switch

    http://www.ebay.com.au/itm/Four-Way-Blade-lever-Switch-Fits-Fender-Tele-4-Position-/281308549333?hash=item417f4bd0d5:g:9o4AAOSw5ZBWQk8W
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    electronic speed control for drill motor

    If running on AC then a series diode of appropriate size. http://www.ebay.com.au/itm/Stud-Mount-0-4-Male-Thread-ZP-1200V-20A-Power-Rectifier-Tube-Diode-/331642105514?hash=item4d3768eeaa:g:-dQAAOSwoydWq1kn
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    Running three phase delta on single phase

    Single to 3 phase inverter.
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    Running three phase delta on single phase

    Three phase motors have their windings separted 120 electrical degrees apart and require a supply of the same nature. Any capacitor connected arrangement would be theoretical and rather low in torque if at all applied and perhaps require a "hand start" not to mention current characteristics way...
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    AC motor speed controller as a regulated transformer?

    30v 5A would be costly especially if you build yourself especially the transformer. One for 30V 150VA would probably be around the Aus$100 plus any handling etc. Most linear regulators can handle up to 1A (maybe on a heatsink) but you start going higher than that for a simple laypout and you...
  8. B

    AC motor speed controller as a regulated transformer?

    I think the op is trending at a bench power supply. i.e. thyristor clipped mains cable lying around on the bench.
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    AC motor speed controller as a regulated transformer?

    Transformer would be ok. Whether you need a full bridge or not depends on the transformer secondary tappings. Any connections with the mains should be checked by your local electrician before use and run the gear on a safety switch. As for control over the voltage, use an adjustable 3 terminal...
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    AC motor speed controller as a regulated transformer?

    No...you'll end up killing someone.
  11. B

    AC motor speed controller as a regulated transformer?

    More detail on what you intend to use it for/with.
  12. B

    Arduino Help... Error : "The programmer is not responding"

    What board did you use for rs485? Suspect you may have blown your board as these pins are not to be used (at least) for rs232 as voltage is too high.
  13. B

    Part substitution.

    Did you notice the pin configuration between the BC517 and the MPSA14 is different?
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    Transistor hfe

    Depends how soon one tests after it's come from the charger.
  15. B

    Transistor hfe

    Maybe because a car battery voltage can vary anywhere between 11.4v and 12.8v and at 30A I'd be pretty sure the output would go below 12V hence the regulator and 2 car batteries.
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    12v timed switch query

    Probably....difficult to say as the link they provide doesn't show what they claim(circuit) As I said before, plenty of free stuff at Talking Electronics with tutorials, books etc. explanations for all you need to know. http://www.talkingelectronics.com/te_interactive_index.html Run down the...
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    Transistor hfe

    Original circuit details here........ http://www.zen22142.zen.co.uk/Circuits/Power/1230psu.htm
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    Transistor hfe

    Gain is just a number not 1000mA as you say. Basically the possible amplification ratio. Reason it is high is the transistor is a darlington arrangement where the gain of the first is multiplied by the gain of the second to get the final result. It means that relative small signals can feed the...
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    12v timed switch query

    Difficult to translate the broken Chinese/English but it appears the unit you show would start to operate when power was applied at the 2 terminal input. You could use a pushbutton but you would have to hold it on for more than the time period. You could use a toggle switch instead and simply...
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    Help with PIR Light circuit

    Do not know what type of sensor you have BUT many of the China versions are able to do just that. Operation is by the line control switch. Turn on and leave on = automatic (timer). When the control switch is operated it first switches the light on and after a settling time the light goes out and...
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