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  1. Audioguru

    9v Guitar Amp w/out LM386

    The employer asked this "digital" worker to make an analog circuit using discrete parts. Maybe for the worker to learn how to find or ask for a circuit on the internet instead of learning how to design the circuit.
  2. Audioguru

    Help with Binary Counter circuit - Doesn't seem to respond to clock.

    Each of the old fashioned TTL ICs needs a power supply decoupling capacitor mounted very close to it. Your circuit has no capacitors, no schematic and nothing showing a clock oscillator.
  3. Audioguru

    Partialy Discharging Capacitor

    Your understanding of voltage and brightness is backwards. When the main voltage for an xenon tube is halved then the power and brightness are 1/4 times. If the main voltage is doubled then the brightness and power are 4 times. Your trigger circuit must not have its voltage reduced when the...
  4. Audioguru

    Led light strip connected to subwoofer amplifier power in?

    Your LED strips will use 9.5A from a dead 12V battery. The current will be a little higher when the engine is charging the battery at 14.4V. The huge fuse will not notice only 9.5A. I think there is a huge fuse because if the car is in an accident that shorts the wiring then the fuse will blow...
  5. Audioguru

    Noob? Electronic car horn for bicycle

    The TDA7052A is also not available anymore. The TDA7052AT is also not made anymore but some distributors still have some. It is tiny and will melt if the speaker is less than 16 ohms and if the supply is higher than 6V. It is different than the original TDA7052 because it has a built-in volume...
  6. Audioguru

    Led light strip connected to subwoofer amplifier power in?

    If your amplifier is powered from 13V and has a 250A fuse then the fuse will blow when the output power including amplifier heating is 13V x 250A= 3250W! Why such a high A fuse rating? The Datasheet for the LED strips will say how little current they use.
  7. Audioguru

    Noob? Electronic car horn for bicycle

    1) The TDA7052 is not available anymore in a thorough-holes package, instead it is available in a tiny surface-mount package that will overheat when powered from 6V or more when driving an 8 ohm speaker. The TDA7052AT in the tiny package is shown in its datasheet with fairly low output power...
  8. Audioguru

    LM358n issue

    Most opamps are not power amplifiers, they cannot produce much output current. The datasheet for an LM358 shows that when the output current is 10mA then the maximum output voltage for a typical one is +10.5V when the supply is 12V and some LM358 opamps have more voltage loss. A little...
  9. Audioguru

    LM358n issue

    The datasheet of every opamp shows its output voltage swing. For an LM358 with a +12V supply and a load current of 10mA then its typical maximum output voltage is +10.5V. When the load current of a typical LM358 is about 35mA (about 171 ohms to ground) then its maximum output voltage is about...
  10. Audioguru

    Building Portable AC power supply

    If you use 110VDC to make an inverter then its output will be a crude squarewave that you would not want to use to power an audio amp or a video projector. Mains electricity is a pure sinewave with few harmonics and its peak voltage is 155.5V for your low voltage 110VAC or the peak voltage is...
  11. Audioguru

    Need Help With Designing A Lithium Ion Battery Powered Delayed Power On Circuit

    No. A Lithium-ion 18650 cell is fully charged at 4.20V, is 3.7V when in storage or halfway in a discharge and is about 3.2V when it is almost dead and its load should be disconnected.
  12. Audioguru

    LM338 CC/CV

    You talk like you have never seen the datasheet of the LM338. Datasheets have all the spec's and most application circuits. The LM338 minimum output voltage is about 1.2V but of you add a -1.2V supply it will go down to about 0V. Its output is guaranteed to go as high as 5A but two in parallel...
  13. Audioguru

    Question on LM317 based high current voltage regulator

    Your circuit is missing the important input and output capacitors shown on the datasheet of the LM317. Your 220 ohms for R2 is for the more expensive LM117. 120 ohms is needed fore the LM317 so that the output voltage does not rise when the load current is low. Then the value of the pot must be...
  14. Audioguru

    Decade Counter

    The circuit is too simple. 1) Pin 14 is floating but it MUST have a resistor to GND. 2) When power is applied, the counter can begin at any count. Maybe it begins at count 7, 8, 9 or 10 then your button will seem like it does nothing. Add a "power-up reset" circuit with a capacitor and...
  15. Audioguru

    Trying to power late grandmother's portable TV

    I haven't used D size battery cells since about 50 years ago. The datasheet for an Eveready Super Heavy Duty carbon zinc D cell shows that it could provide 800mA for 2.5 hours. Select a 12V/1A power supply.
  16. Audioguru

    Circiut knight rider

    Instead of the outputs fighting each other through the resistors, diodes should be used to replace the resistors. Google shows many circuits with the diodes.
  17. Audioguru

    Ultra Compact 12v DC power supply and superbright led's.

    The chemistry and size of a battery determines how much current it can produce for a certain amount of time. The voltage from many types of batteries drops as they run down which will cause the brightness of simple LED strips to become dimmer and dimmer. The LED strips you linked to show they...
  18. Audioguru

    problems with P channel mosfet

    Why are your images weird-looking negatives?? The output Mosfets are never turned off.
  19. Audioguru

    Ultra Compact 12v DC power supply and superbright led's.

    A light strip uses tiny low power LEDs. Larger LEDs with much higher power ratings make much more light but they get hot and need a heatsink that maybe you do not have space for. LED streetlights use many large LEDs that are mounted on a big heatsink. Will the power supply be plugged into...
  20. Audioguru

    Need help with this certain circuit (RC phase shift system)

    Every transistor has a part number. Yours does not have a part number. The datasheet for the transistor lists its specifications so that you can bias it properly. You don't have the datasheet. Maybe you are not learning about electronics. Instead maybe you are learning about how to solder wires...
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