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  1. Alec_t

    increasing voltage or current

    LEDs have a forward voltage (Vf) which depends on the colour. Typical Vf voltages are e.g. 1.8V for a red LED, 2.1V for a green, 3.1V for a white. By connecting different colours in parallel the lowest Vf will dominate and effectively 'short out' the other colours. So you would expect...
  2. Alec_t

    increasing voltage or current

    Welcome to EP! Connecting six LEDs in series would be preferable to connecting them in parallel. What is the supply voltage of your circuit? Do you have any other supplies available? What colour are the LEDs?
  3. Alec_t

    Seeking help on circuit design for LED rudder indicator

    This mod should do the trick (only the relevant circuit part is shown). For the simulation I've assumed the rudder pot travel is 50 degrees either side of centre and that the pot resistance track end-to-end extends over 240 degrees (your mileage may vary). A couple of trimmers allow for...
  4. Alec_t

    Convert uneven pulses

    Effectively. It's rather like Minder was saying: the first pulse alerts the Arduino.
  5. Alec_t

    AC Circuit Problem HELP. Urgent.

    Post you attempts so far, so that we can give guidance.
  6. Alec_t

    Seeking help on circuit design for LED rudder indicator

    The posted circuit assumes the pot has end-to-end travel. If travel is only 100 degrees (presumably 50 left and 50 right) you could avoid the need for gears by changing some of the fixed resistor values. A different pot wouldn't really help. I'll re-run the sim and see if I can come up with a...
  7. Alec_t

    Convert uneven pulses

    If every number dialled has the same uneven character, can't you simply ignore the first pulse?
  8. Alec_t

    Seeking help on circuit design for LED rudder indicator

    Nice find. I've simulated that circuit on a 5V supply and it's fine. For a ~10mA LED current make R1=R1'=R2=1k2, and R2'=3k9. 22k is a standard value for the pull-up resistor from pin 11 of the first LM3914.
  9. Alec_t

    Seeking help on circuit design for LED rudder indicator

    Welcome to EP! If you're happy with 5 LEDs in each direction then an LM3914 and a pot, plus a few bits, are about all you need.
  10. Alec_t

    Microsoft excel

    Which market? I doubt that anything M$ produces is open source :D.
  11. Alec_t

    Need help with circuit design

    A cap in parallel with the motor would make hardly any difference on start-up and not much on stop, unless it had a humongous value.
  12. Alec_t

    Philips DVP3042 Distorted black and white video, not reading discs

    Definitely sounds like a power supply problem. Have you checked the usual culprits (electrolytic caps, mains rectifier etc)? Any sign of over-heating, scorch marks?
  13. Alec_t

    Hello from Belgium

    Hi, Edouard. Welcome!
  14. Alec_t

    Timer with NE555

    A 555 timer works at low voltage, low current, whereas your washing machine works at mains voltage, high current. Messing about with mains voltage is dangerous, especially if you are inexperienced. The 555 would need a low voltage power supply, plus a mechanical or solid state relay to handle...
  15. Alec_t

    Neon lamp for turntable repair

    As requested :- This shows two alternatives. The 'fairly high voltage' duke37 mentions is 10VRMS AC in the sim, since going by the 16V rating of C901 in the power supply, that's what I guess the transformer secondary outputs.
  16. Alec_t

    Neon lamp for turntable repair

    Depends how the LEDs are used. If driven by just the rectified AC they will fade in and out rather than flash briefly. They can easily be made to flash, however, with a simple circuit like this:-
  17. Alec_t

    Neon lamp for turntable repair

    That neon is connected directly to mains voltage if the transformer has the D-type strapping. Having it's terminal(s) exposed as shown in the pic is potentially dangerous. Safer to use LED illumination as duke37 says. A pair of back-to-back LEDs (with suitable current-limiting resistor) could...
  18. Alec_t

    wiring a LED lit rocker switch

    Perhaps this will help. Welcome to EP!
  19. Alec_t

    What is the name for those plastic clamshells ??

    Google 'mains junction boxes' and check the images.
  20. Alec_t

    Output of the alternator

    That would depend on whether the fans had power factor correction built in. If not, then the load would be predominantly inductive unless any start/run capacitor capacitance over-rode that.
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