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  1. KrisBlueNZ

    Changing strobe pattern?

    Yes but I would go for one higher than the 1N5404 such as the 1N5407 (1000V). If you can't get one higher than 1N5404 the 1N5402 would do at a pinch. You want plenty of protection from voltage surges.
  2. KrisBlueNZ

    Delay timer circuit for a motor.

    That circuit won't run the motor directly because the 555's output is rated for a maximum output current of 200 mA and your motor presumably needs more than that. If that's the case, you'll also need a bigger battery than a little PP3. Heavy loads can be switched using transistors or MOSFETs...
  3. KrisBlueNZ

    Power Supply Capacitors

    If you can afford them, then sure, use those!
  4. KrisBlueNZ

    Dehumidifer - Does not Power On. Faulty Power Supply Board.

    You're welcome :-) You may find it easier to get an 8.2Ω resistor. That's a standard value and it will be just as good as 8.5Ω. The wattage should be 2.5W or 3W to ensure it will fail quickly and cleanly. Yes, it does have to be fusible. It has to be designed to fail quickly and safely. That's...
  5. KrisBlueNZ

    555 timer circuit

    No. I like to help but I know when I'm being taken advantage of! I think you should have a look at Supercap2F's circuit design, and my code, in the thread I linked to in post #23. Most of what you want is there. There's a list of packages you can use to create your schematic and PCB layout at...
  6. KrisBlueNZ

    Audio Amplifier problem

    I could, but it's already been done...
  7. KrisBlueNZ

    Changing strobe pattern?

    Yeah, their shipping charges are excessive. From the TC4467/8/9 data sheet: So the CPD and EPD suffixes are both through-hole packages, with different temperature ranges. Actually according to that document, the EPD doesn't exist, because the E temperature range applies to the ceramic DIP...
  8. KrisBlueNZ

    Dehumidifer - Does not Power On. Faulty Power Supply Board.

    Congratulations :) You're welcome :) What does the multimeter display on ohms range when you short the probes together? They don't normally display 0.0Ω. If it displays 1.0Ω when you short the probes together, then it always indicates 1Ω higher than the true resistance, so in that case, the...
  9. KrisBlueNZ

    555 timer circuit

    P.S. Look at this thread, there are some ideas that may interest you. Skim all the way through. https://www.electronicspoint.com/threads/chicken-coop-door-opener.269668
  10. KrisBlueNZ

    555 timer circuit

    That's a great description, thanks! And you want the time to be adjustable from 1 hour to 12 hours? I don't think you'll find any switching option cheaper than a relay. This one is USD 1.26 in 1-up quantities: http://www.digikey.com/product-detail/en/G5T-1A%20DC5/Z2774-ND/1731474 I assume...
  11. KrisBlueNZ

    555 timer circuit

    No, but I will draw something up if you tell me in detail what you want to use it for. This is so I can make judgement calls about how it should behave.
  12. KrisBlueNZ

    555 timer circuit

    Not reliably, no.
  13. KrisBlueNZ

    design score broad for a game

    I suggest you use N-channel MOSFETs driving common anode displays. This allows you to power the displays from a higher DC voltage than the rest of the circuit, which may be necessary if the large displays contain several LEDs in series for each segment. Also, N-channel MOSFETs have better...
  14. KrisBlueNZ

    555 timer circuit

    Each 555 needs a decoupling capacitor of around 0.1 μF ceramic, connected as closely and directly as possible between pin 8 and pin 1, for reliable operation. See the data sheet for more information. The first 555 (not just the second 555) needs a decoupling capacitor of around 10 nF ceramic...
  15. KrisBlueNZ

    What is the difference between Flash and PROM?

    I should have said, to summarise, that EEPROM is used for data storage under program control, and Flash ROM is used for code to be executed directly by the MCU.
  16. KrisBlueNZ

    What is the difference between Flash and PROM?

    EEPROMs and Flash ROMs are both electrically erasable and reprogrammable. The differences are that EEPROMs are normally smaller than Flash ROMs; they are normally accessed serially (which is relatively slow) instead of in parallel like Flash ROMs; and they are erased and reprogrammed using a...
  17. KrisBlueNZ

    555 timer circuit

    Upload a full and correct schematic of what you have that doesn't work. Otherwise we really don't know what you're doing.
  18. KrisBlueNZ

    Decoupling capacitors

    I would always use what the data sheet recommends, unless I thought I knew more than the authors of the data sheet!
  19. KrisBlueNZ

    Power Supply Capacitors

    ESR won't be an issue but bear in mind that while the toobs are warming up there will be no load on the HT and the voltage could be as much as 50% higher than the final operating voltage, possibly even more than that, for 10~15 seconds. So I would be very generous with the voltage ratings of the...
  20. KrisBlueNZ

    Stage Line 500W amp repair project

    I'm sorry to hear that. I hope you're feeling better now. I need two more voltages.
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