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  1. Audioguru

    Need help interpreting something on a schematic

    Another old circuit using an obsolete opamp. It produces the same distortion as all the other overdrive circuits you posted. The opamp is not powered so it will not work. It also will not work if it is powered by one 9V battery and the guitar pickup grounds its input. The circuit assumes that...
  2. Audioguru

    25 PF Capacitor sub

    The 27pF capacitor parallel with the 1M opamp's negative-feedback resistor simply cuts audio frequencies above 1 divided by (2 x pi x 27uu x 1M)= 5926Hz at -3dB, making sounds a little muffled. R6 and C5 also cut frequencies above 1 divided by (2 x pi x 10k x 1nF)= 16kHz at -3dB. I never...
  3. Audioguru

    tinning

    I tin stranded wire to hold together the strands. My soldering iron is temperature controlled and is always at the correct temperature. Cheap soldering irons, even ones with a light dimmer circuit get too hot which incinerates the rosin in the solder. I always use Name-Brand solder not the cheap...
  4. Audioguru

    9014 Direct Replacement???

    The datasheet of an IRF5305 Mosfet and most other Mosfets shows that its gate must be at least 10V higher than its source for it to fully turn on. An ordinary power transistor base must be only about 1V higher. You have not said the amount of maximum current the transistors drive into how many...
  5. Audioguru

    Battery ruined by diode and LED

    Hevans, you have been through a lot. 20 years ago I quit smoking. I never tried vaping. 11 years ago I had a heart attack and was fixed with 2 stents. My performance was good in the rehab class. 6 years ago I quit drinking alcohol. For the past few years I feel and act 45 years old (young?)...
  6. Audioguru

    Your Problem Solving Method

    When the power supply pins on an IC are connected with backwards polarity then the battery is shorted by the IC. When cheap Chinese fake or defective ICs are powered then they might short the battery. Many "pedal" circuits use the input or output jack as a power supply switch that could short...
  7. Audioguru

    Looking for a suitable universal charger for a variety of electronics

    Do you want a complicated charger designed for charging a battery that has a certain chemistry? Or do you want a simple power supply? They are very different. If you use a power supply instead of a proper charger then you might have an explosion or fire from the battery. If you use a charger...
  8. Audioguru

    Battery ruined by diode and LED

    You added a diode in series with the battery but the diode is shown connected backwards. You said the ecig and LED worked but the battery would not charge anymore. If the diode was the not backwards then it reduced the charging and battery voltages so low that the battery was barely charged only...
  9. Audioguru

    Battery ruined by diode and LED

    A Lithium 18650 battery is charged to a maximum of 4.2V. Its charger is powered from 5V. The charger should have an LED that lights when charging and shuts off when it detects the battery is fully charged.
  10. Audioguru

    Capacitor Swap

    The obsolete transistor (you can use two common transistors wired like in the darlington transistor symbol) is drawn wrong and is actually a darlington. What a horrible circuit, but it might make a unique kind of severe distortion. The 47uF capacitor does not pass audio, instead it shorts it to...
  11. Audioguru

    A Stretch

    Believe by Cher used obvious Auto-tune and so does rap by Drake. Many unmusical people do not know what is "being in tune".
  12. Audioguru

    A Stretch

    Also, there are too many "singers" today who cannot sing worth a damn. They read the lyrics while auto-tune does the singing for them.
  13. Audioguru

    A Stretch

    The bridge on a banjo is mounted on the skin on front which is like a drum-head and sounds different to the wood bridge of a guitar.
  14. Audioguru

    The corona. What's the latest?

    United States has 10 times the population that Canada has but US has 100 times more Covid-19 infections. Crowded conditions in religious gatherings, bars and beaches are where the fools are passing the virus around.
  15. Audioguru

    A Stretch

    I can play millions of MP3 songs but not your guitar in the "cloud".
  16. Audioguru

    DC voltage blocker - Blocking AC too?

    The AC is destroying the LED because its maximum allowed reverse voltage is only 5VDC. The 9V AC has a peak voltage of 9V x 1.414= 12.7V The LED might be a 2V red one then the capacitor charges to +10.7V. The AC produces negative peaks of -12.7V then the LED gets reverse voltage pulses of 12.7V...
  17. Audioguru

    A Stretch

    Horray! I am glad to see that you got it to sound as awful as you want. Oh, without the diodes that cause the distortion? Then i guess you have the opamp clipping its head off.
  18. Audioguru

    A Stretch

    The circuit designer does not know how to calculate the value of a coupling capacitor or he made a typo. The 4.7uF capacitor C4 passes earthquake frequencies down to 3.4Hz through the 10k resistor R6 into the diodes. A 330nF film capacitor (marked 334) will pass music frequencies down to 48Hz...
  19. Audioguru

    9014 Direct Replacement???

    The part number of the transistor depends on the amount of voltage and current the LEDs use. The voltage and current for the LEDs depends on their color and part number, how bright you want them and how many you will have.
  20. Audioguru

    A Stretch

    The 4558 is also old and is an "improved" dual 741 opamp. Its high frequency bandwidth goes up to 40kHz (the 741 goes up to 9kHz) and it produces fairly low noise (the 741 is so noisy that the datasheet does not say how much). The 4558 has a recommended 10V minimum supply voltage. Your 9V...
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