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  1. KrisBlueNZ

    Chicken Coop Door Opener

    Hmm. I'm not sure. I think that would be OK.
  2. KrisBlueNZ

    How to have a single switch to open/close several lines at the same time

    Why don't you just explain the whole project. What are these signals used for? Why do you want to switch them? What's the whole project about? Really, you wouldn't ask a friend to solve a jigsaw puzzle for you by showing them a picture of just a few of the pieces, would you? Why keep us in the...
  3. KrisBlueNZ

    Hello all

    Hi Matt and welcome to Electronics Point :-) Electronics is a great hobby and/or profession to be involved in. So much that's interesting and fun. I hope we will be able to help you make the most of it!
  4. KrisBlueNZ

    Chicken Coop Door Opener

    A few metres should be fine. Just keep the wires away from other wiring and appliances.
  5. KrisBlueNZ

    Power issues with latches

    Well, the CD4013 is much more commonly used, but you only get two latches per package, not four. Also, the set and reset inputs are active high (like the 4043, which is like the 4044 but with active high inputs instead of active low inputs). I guess the 4000 series is all close to obsolete now...
  6. KrisBlueNZ

    Need heat sink for GBU806 bridge rectifier

    Yeah, I would find or buy a thick bit of aluminium and cut it to shape by hand.
  7. KrisBlueNZ

    How to have a single switch to open/close several lines at the same time

    What are these "contact lines" carrying? Is it high voltages? Low voltages? Signals? What kind? You can get relays with as many as four changeover contacts; beyond that, the prices start to go crazy. Your cheapest option would be nine DPDT relays. These are available in pretty small packages...
  8. KrisBlueNZ

    Strange voltage reading from AC adapter

    Good :-)
  9. KrisBlueNZ

    Repairing a Sony D-25 Discman

    Hmm. I've searched for the service manual but no luck. If there's no obvious damage, and no documentation, I wouldn't know where to start. The chip under the sticker is sure to be a Sony custom part, probably also undocumented. It's over 20 years old now, so there's a good chance the laser is...
  10. KrisBlueNZ

    Strange voltage reading from AC adapter

    Some people call all adapters "AC" adapters, whether their outputs are AC or DC, because the mains wall power is AC. I don't think there's a consensus on the right name for them. This is a 19V DC adapter for a laptop. We don't know whether the problem is in the power supply or the laptop. It's...
  11. KrisBlueNZ

    Power issues with latches

    Sounds like you may have floating inputs. CMOS inputs are very high-impedance, so if they aren't connected (or pulled, with a resistor) to a known voltage level, they will float, assume random states, and pick up noise. Why the CD4044? It's a pretty uncommon device.
  12. KrisBlueNZ

    Greetings!

    Hi there and welcome to Electronics Point :-) I hope we'll be able to help!
  13. KrisBlueNZ

    Sound to light for my son's Dalek

    I suggested a 1N4004, not a 1N4148. 1N4148 is only rated for 100~200 mA (depending on manufacturer) and is not a power diode. Try 2200 µF for C4. But also check the topology of your connections, as I mentioned before. The whole path from the positive side of the power supply, through the bulbs...
  14. KrisBlueNZ

    Old tractor ignition upgrade problem

    FYI a "monoflop" is normally called a "monostable" or "one-shot".
  15. KrisBlueNZ

    Safe USB battery extender

    Harald, I think the overcharging danger may relate to the battery in the USB charger, not the battery in the tablet.
  16. KrisBlueNZ

    Sound to light for my son's Dalek

    OK. Replace R5 with a diode such as 1N4004, pointing leftwards (i.e. anode to battery positive, cathode to the small-signal circuitry). You may also need to increase C4. That should solve the problem, but if not, you could add a regulator in there. I recommend a low dropout regulator such as the...
  17. KrisBlueNZ

    answer this little question

    OK, your question is unclear and I suspect you don't have a clear understanding of what is being asked. I've been trying to figure out what the question is about. This is what I think. Phase 1 and Table 1 relate to two or three resistors in parallel, connected across a 2.1V voltage source. The...
  18. KrisBlueNZ

    television freq scanning

    I don't think there's any point trying to change the tuning range because there won't be any TV channels outside the standard frequency bands.
  19. KrisBlueNZ

    Sound to light for my son's Dalek

    OK. When you try the relay, try it with and without the lamps. If there's a difference in behaviour, that implies there's something happening to the power supply voltage when the lamps are present. The MOSFET gate voltage is pulled to 0V by R11. You could check that it's present, the right...
  20. KrisBlueNZ

    Advice for starting a Project (Heat sensor switch)

    Yes, that design is spot on. Re the wiring. I would make all the connections at the thermostat board. Run a separate twin cable to each fan to the thermostat board. And you will have a third twin cable from the power supply. All six wires can be terminated into the plugs that plug into the...
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