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  1. B

    Need help using Nichrome wire for a foam cutter

    mmm...well, I've never seen anyone twist cutter wire lengths together to get to the end result. Too much mucking around and the result is at best, iffy. Simple matter to supply a transformer of appropriate size for maximum expected (as I've already quoted) and control the output quite easily...
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    Need help using Nichrome wire for a foam cutter

    It's not rocket science just simple E=IR. So the Op can see easily, I have shown 2 examples below. The nichrome is represented by series resistor values and how the change in length or nichrome wire diameter changes this resistance. Then how to increase the voltage to overcome the difference.
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    (NiCD bat device) - What TM Resistor? Polarities?

    There appears to be more to this in a particular publication from 1986. In any case it appears to be directly connected to mains supply so best to avoid as it would be a dangerous arrangement.
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    Need help using Nichrome wire for a foam cutter

    Agreed....
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    AC generator

    Wow...100w light bulb from an input which appears to be a rather large drill...maybe 700 watts or more?
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    Help! Transistor radio converted into amp

    It may be low voltage but the caps can store a charge enough to give one a surprising wack.
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    Light Bulb Technology?

    Photo is of one of the latest trends in downlights. Mostly around 10W. If no heat dissipated as you claim, then why the rather large heatsink? Not the LED...mmm how about the driver.
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    How to prevent current feedback in a circuit with dual supply

    Most auto headlight systems are not wired the way you show, they are constant power fed with return switching. Can get complicated unless one starts with the correct wiring.
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    Alternative Actuator Choices?

    What sort of forces do you expect to deliver and what space requirements. Maybe some more detail on power input type etc.
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    Need help using Nichrome wire for a foam cutter

    Ian, I just took a look at the transformer I used to use to cut foam cores for model aircraft. Mark was on the money with his reply and I'll give you some of the details of the system I have here. Transformer I use is a Ferguson which came from an ice making machine. Windings are 2 x 20V...
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    Help! Transistor radio converted into amp

    In a mains connected device, when you disconnect the power there still may remain some charge in the power supply capacitors that can give you quite a nasty belt. However, the point about using a battery powered radio was that there may be some smoke if you do any modifications incorrectly. But...
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    AC generator

    None.... some reading for you here http://avstop.com/ac/apgeneral/typesofacmotors.html
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    Help! Transistor radio converted into amp

    My reference to using a battery type radio was to keep you well away from any mains supply, whether it is working on the device or not. There is a possibility you could inadvertantly connect into the wrong part and do yourself or others an injury.
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    Trying to figure out the problem on a drive thru sensor.

    Looks like a 2 way intercom.....maybe a speaker inside the cone.
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    Uprate a model servo

    H bridge intro..... http://www.pyroelectro.com/tutorials/h_bridge_4_transistor/
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    Help! Transistor radio converted into amp

    Maybe like this....and please use a battery radio...keep away from mains type.
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    Uprate a model servo

    Servos, even from the same manufacturer, vary quite a bit depending on the age. It would be possible for some to take the clockwise/counterclockwise signal from the servo controller chip and feed into a larger H-bridge to drive your 6v motor. Also input your 8 turn feedback device to the same...
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    How to get started with electronics ?

    Have a look here...just an example of what is out there in Google land... Plenty of free stuff at this place.. http://www.talkingelectronics.com/te_interactive_index.html
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    motor driving: sane?...

    Hope you used ballast resistors on those parallel 3055 transistors......
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    DC short circuit calculation formula for copper busbar

    mmm...seen my share of switchboard testing and have to agree.
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