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  1. Audioguru

    Will a voltage divider waste power?

    Why do you have a useless high voltage spark gap powered from expensive high voltage resistors that reduce the voltage? What high voltage load do you have that uses an expensive high voltage capacitor parallel with it to filter away current pulses created by the spark gap? How will you prevent...
  2. Audioguru

    Will a voltage divider waste power?

    If the load resistance cannot be higher than R2 then R2 will do nothing but waste power instead of regulating the reduced voltage. A capacitor will not regulate the voltage but can filter it.
  3. Audioguru

    Will a voltage divider waste power?

    Why can't you properly sketch and properly describe what you talk about? Maybe this is what you mean:
  4. Audioguru

    Will a voltage divider waste power?

    A voltage divider does not have its output shorted like that. Here is a real voltage divider and here is your shorted circuit:
  5. Audioguru

    Will a voltage divider waste power?

    When you short the resistor then there is no voltage divider and there is no load. Without having a load then a bypass capacitor is not needed.
  6. Audioguru

    Help with 555 latch circuit

    Your ICM7555 is a Cmos 555 that is completely different to an ordinary NE555 or LM555. It has a low output current that is loaded down with the LED current. It will probably work if you add an NPN emitter-follower to its output to drive the LED.
  7. Audioguru

    How come these alligator clips only transfer electricity when swapped at the battery terminals?

    Years ago I was a technician on the car radio production line. The radios had a huge reversed diode directly across the supply to blow the car's fuse if the radio power polarity was connected backwards by an idiot. A series diode was not used because it would reduce the radio's maximum output power.
  8. Audioguru

    replacing two D cells with pair of 18650 batteries but need voltage drop

    Eneloop does not make a 9V battery. Energizer 9V Ni-MH battery does not have the new LED Eneloop chemistry.
  9. Audioguru

    How come these alligator clips only transfer electricity when swapped at the battery terminals?

    Barrel connectors like you showed are connected with both polarities but usually show a sketch of the polarity used. The protection diode is called an "idiot diode" because only an idiot will connect the polarity backwards.
  10. Audioguru

    Will a voltage divider waste power?

    A dead short is one "of the pathways just leads back to the battery again". It wastes ALL the battery's power. A series resistance wastes power. A series resistance and a resistance to ground (in a voltage divider) has both resistors wasting power. A series resistor and a voltage divider produce...
  11. Audioguru

    How to limit amplifier output power

    An amplifier with a +/-40V supply has a total of 80V which will allow an amplifier output of about 80W into 8 ohms per channel before clipping or 100 Whats with severe distortion. The output will be about 140W into 4 ohms if the amplifier can drive 4 ohms. I blew up the woofers in speakers rated...
  12. Audioguru

    Why is it PNP instead of PPN for transistors

    Coil and magnet speakers are made to play AC sounds. You are probably frying them with DC. Many You Tube videos about electronics are completely wrong and are made by kids who get paid by You Tube each time somebody views an ad before the video.
  13. Audioguru

    Why is it PNP instead of PPN for transistors

    A piezo speaker is very small so it produces only high frequencies. It has strong resonances at some frequencies and low output between resonant frequencies. It is made for a beeper. Impedance is the resistance at an AC frequency. Because a coil and magnet speaker is an inductor its impedance...
  14. Audioguru

    Why is it PNP instead of PPN for transistors

    Why talk about making an audio LC oscillator with a extremely high value capacitor and a fairly low value inductor? No schematic for us to see if it can produce enough output power to drive a speaker. Also your speaker has no impedance and no power rating.
  15. Audioguru

    Woo-Woo passive amplification using an lc oscillator

    Your simple circuit is not an oscillator. If you connect an amplifier output to the capacitor then the amplifier output will be shorted when the amplifier plays high frequencies. The signal is not boosted. Maybe you need a speaker crossover circuit:
  16. Audioguru

    replacing two D cells with pair of 18650 batteries but need voltage drop

    I figure that LSD Ni-MH cells are Low Self Discharge. Sanyo/Panasonic Eneloop batteries are expensive. I am glad to find that Tenergy Li-Ion batteries are not the Chinese Ternigy Li-PO batteries I had a bad experience with and Chinese low capacity Duracell Ni-MH batteries. I recommend Energizer...
  17. Audioguru

    QSC Power Amp gets hot

    Was one channel always too hot because the bias trimpot was set wrong or did the trimpot get bumped and accidently changed? Or did a transistor's conduction change?
  18. Audioguru

    QSC Power Amp gets hot

    Simply turn the trimpot a little and see if the voltage and current change.
  19. Audioguru

    QSC Power Amp gets hot

    I think the trimpot wiper makes poor contact with the resistive track.
  20. Audioguru

    LM339/LM339N can't get output high

    The datasheet for an LM339 comparator does not say if the output has the same polarity as the + input. The schematic of the same oscillator in both datasheets shows that their output polarities are the same.
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