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  1. Herschel Peeler

    Trying to make a transistor cancel another transistor

    Or, if you just wanted to work a PNP transistor into the scheme ... Sw 4 controls the LEDs unless Sw 5 is open.
  2. Herschel Peeler

    Trying to make a transistor cancel another transistor

    Something like Steve suggested. Sw 4 controls the LEDs, one off and one on, following the switch. Sw 5 defeating the operation, forcing one condition.
  3. Herschel Peeler

    Trying to make a transistor cancel another transistor

    Circuit as Alec suggested. Sw 4 controls the LED unless Sw 5 is on.
  4. Herschel Peeler

    Trying to make a transistor cancel another transistor

    One step at a time. This is what your original drawing looks like. Switches 1 and 3 must be on before LED 2 comes on. Switch 2 must be on before switch 3 can come on.
  5. Herschel Peeler

    Just saying 'hello'

    Projects? Music related?
  6. Herschel Peeler

    Component equivalent

    30 V, 300 mA, 200 mW ... gain of 1,500 is going to be the problem. (edited to add ...) http://au.rs-online.com/web/p/bipolar-transistors/6638581/ $0.19 each, but you have to buy a pack of 10.
  7. Herschel Peeler

    Switching leds

    That looks good if the LED is actually common anode. I can't find one in my library either. All are common cathode.
  8. Herschel Peeler

    Power supply + and -

    Pinout can vary with the case style, too.
  9. Herschel Peeler

    List of older 74xx devices

    2016 list is good. My list is more for those repairing stuff and need the old stuff as well as the new. Otherwise it is educational. Most material covers basic gates and latches/. Mine covers 74xx series VCO's memories, rate multipliers, delay lines, as well as bit slice processors. And yes xx...
  10. Herschel Peeler

    Resistors

    First find total resistance.
  11. Herschel Peeler

    I need a relay or something

    You gave a trailer wiring without a brake light going through it?
  12. Herschel Peeler

    LED pucks getting hot

    The link for the lights doesn't indicate normal current at 12 V. Running at 13 V they could draw excessive current the result of higher current and higher voltage means lots more power. They are dimmable? A dimmer might be your answer.
  13. Herschel Peeler

    List of CMOS digital devices, CD4xxx

    I remember those days. The RCA data book called the line COSMOS. We been around a long time.
  14. Herschel Peeler

    Led's headlight issue

    I found a video on youtube of a guy replacing the bulbs and that's all he did. No problem mentioned.
  15. Herschel Peeler

    Led's headlight issue

    Can you contact the manufacturer of the LED? This isn't likely a new problem to them.
  16. Herschel Peeler

    List of CMOS digital devices, CD4xxx

    Included are devices in the 74xx family greater than 6000. .
  17. Herschel Peeler

    List of older 74xx devices

    This is an older list (2014). Let me know if I missed anything. 74xx devices greater than 6000 are in the CMOS (CD4xxx) devices list posted elsewhere.
  18. Herschel Peeler

    How can i add a trigger to this circuit to make it not electrocute the user?

    Ah, I see. Connect it in as SW2. The circuit you have is good and safe.
  19. Herschel Peeler

    How can i add a trigger to this circuit to make it not electrocute the user?

    Very true, especially if not trying to drive following logic also. But an LED alone to 9 V seems unreliable.
  20. Herschel Peeler

    How can i add a trigger to this circuit to make it not electrocute the user?

    2K to 3.6K for the resistor. High out for the chip is about 2 mA at 9 V. The LEDs will probably light okay at that. Since only one LED will be on at any time you could just use one resistor from the common cathode connections to ground. I still don't get what you want to do for a trigger.
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