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  1. B

    Three pins socket

    Should that not be 2 is earth?
  2. B

    Electric motor - one rotation then stop

    Difficult to achieve with any accuracy. Assume a gearbox is attached to the motor to give the 70RPM. If that is the case the motor would have quite a bit of over-run once the power was removed. One could "short" the motor terminals to give an amount of dynamic braking after the power was turned...
  3. B

    Astable 555 Circuit Problem

    you will need 2 555 chips.(or a 556)other possibilities also.(one to create an oscillator) The way it is now, the output switches hard on and off.
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    I need help with a DC voltage regulator circuit

    http://www.ebay.com.au/itm/DC-12V-40V-Motor-Speed-Control-PWM-Controller-w-Knob-10A-Reversible-Regulator-/400725971189?hash=item5d4d2110f5
  5. B

    Dell Lcd backlight inverter.

    Maybe see if youtube has anything on your model.
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    Help mitre saw blows house fuse

    16A is the rating of the plug, not the machine. At 200W it should only draw a couple of amps at startup........ As Adam says, contact the trading standards. I think you will find the seller should have the correct plug already fitted.
  7. B

    Hitachi desk fan capacitor replacement

    Typical fan motor.
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    Simple alternative to 300 deg twist pot

    You could go the way I did (only interchange the gears) when I needed a tacho needle to travel 270 degrees from a servo (60 degrees). Another approach would be as i did on an encoder. Use two shafts with diameters proportional to the ratio of degrees, secure then wrap three or four turns of a...
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    British Electronics correspondence course

    Maybe these guys could help.... http://www.vintage-radio.net/forum/showthread.php?t=62750 http://www.vintage-radio.net/forum/showthread.php?t=62836
  10. B

    Hitachi desk fan capacitor replacement

    Old one is probably paper type and your ceiling fan type will be plastic film but both are used in the start winding. They stay in circuit all the time (no switching) and during startup they help to pull the start winding "out of phase" with respect to the run winding to give the necessary...
  11. B

    Help with a dehydrator

    It is a thermal fuse. The rating at which it blows in degrees should be stamped on the casing. A good fuse will be indicated by closed circuit i.e. near to zero ohms. The new fuse when obtained should have the leads crimped into the circuit as soldering will more than likely blow your new...
  12. B

    Switch and pot replacement for drill motor

    The "trigger" does not change the resistance as you put it. The trigger houses a thyristor which controls the phase angle at which the drill motor is supplied power thereby controlling the speed. You cannot do this with your "pot" which in most cases as stated is about 1/4W power rating. An...
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    Switch and pot replacement for drill motor

    Doesn't work that way. Motor is a series type with brushes to the armature in series with the field coils. To reverse the motor, the switch mechanism connects the brushes one way or the other with respect to to field winding. The switch mechanism also houses a thyristor type phase angle speed...
  14. B

    12V Battery on a 230V/50Hz Pump

    220vac pump is 220vac....no internal inverter as you claim. As far as hacking into a fully sealed pump, not a good idea by any means.
  15. B

    Power for 12v water pump

    Yes but is your replacement power supply AC or DC to match the original.
  16. B

    Amp measuring

    Meter appears to be "auto-ranging" AC tong meter. Reading shown would be 1/4A (00.25A) not 25A and not 25mA.
  17. B

    How do I test these Mosfet ?

  18. B

    Need schematic for a Realistic PA amp Model MPA 20

    https://www.circuitlab.com/circuit/func75/mpa-20-realistic-audio-amp/
  19. B

    a timing circuit

    By the look of that you need more gate voltage, hard to say without knowing component details. Drawing should follow standard drawing practice, i.e. positive rail at the top, negative rail at the bottom, everything else in between. Makes for easier reading and troubleshooting.
  20. B

    Car cigarette lighter

    You won't get that apart, it is a moulded plug, not meant for repair. Best to go to a wrecking yard and pick up another from the same model vehicle.(or buy a new part) Don't know why you cut into there in the first place as the lighter disconnects from the black wire (spade terminal) and the...
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