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  1. Audioguru

    Can you detect leaking batteries electronically?

    Duracell AA alkaline cells leak when discharged. Energizer guarantee no leakage from their AA alkaline cells.
  2. Audioguru

    Milliamp power supply question

    The rated output voltage of a power supply is when it has its rated load. A cheap low current power supply output voltage when its load current is low can be as high as double its voltage rating. Then some of your projects will be destroyed.
  3. Audioguru

    Li-Ion battery question

    Lithium is a metal that is very reactive like magnesium and titanium (they all have "ium") and they burn with a very hot fire. Water on the fire makes it burn hotter.
  4. Audioguru

    Help with 1970's TV!!

    I do not know where you are, but here in Canada broadcast TV is all high definition digital now, an old TV will not work without a converter.
  5. Audioguru

    160 KHz Oscillator Transmitter

    There are many tutorials about transistor crystal oscillators and transistor biasing on the internet.
  6. Audioguru

    Solar Panel running 2x20m RGB strips

    6 or 7 times a year is every 2 months. The 5050 RGB LEDs draw >2A per 5m so total of 30m will cause a current of >12A which will be a pretty big lead-acid battery. Use a charge controller then it will charge the battery in a few days then trickle charge it to keep it charged.
  7. Audioguru

    Solar Panel running 2x20m RGB strips

    My garden has 18 solar garden lights that slowly fade between all the colors of a rainbow, each one separately from the others. Each light uses 0.017W so all together they use 0.3W. Yours will use about 485W which is 1585 times more.
  8. Audioguru

    Solar Panel running 2x20m RGB strips

    LED strips use about 3.7W per foot and 40m is about 131 feet. Then the LEDs use about 3.7 x 131= 485W so the solar panel will be overloaded. The solar panel cannot charge a battery and light the LEDs at the same time. If you light only one color then the solar panel load will be only about 167W...
  9. Audioguru

    Replaced Li battery in headset, but won't charge?

    You posted the same battery ad twice. There are many fake Lithium batteries sold on ebay.
  10. Audioguru

    BC147 transistor equivalent

    NTE simply buys a BC547 and stamps their part number on it after tripling the price. Why don't you use a BC547? it has the same chip (but a newer case) as the BC147.
  11. Audioguru

    Wired, rechargeable battery powered overhead LED lights

    Most reviews say that those LED lights fail soon. Amazon knows nothing about electricity which is why they did not say how much current the lights use.
  12. Audioguru

    BJT AMPLIFIER

    With the input at 1.4V peak and a gain of 8 times then the output will have a peak of 1.4V x 8= 11.2V that needs a supply of more than 11.2V x 2= 22.4V, not 12V. Increase the value of R1 to reduce the gain (or reduce the input signal level) and reduce the value of R6 (for symmetrical clipping)...
  13. Audioguru

    A Welcome to EP For AudioGuru

    Like a transistor with no negative feedback, a tube with no negative feedback produces even harmonics that are "musical". But added harmonics are distortion that should not be present. Even harmonics are when one half of the waveform is squashed, either the positive going (usually) or the...
  14. Audioguru

    A Welcome to EP For AudioGuru

    My first amplifier used tubes and was a Heathkit about 53 years ago. It sounded good for a month or two then the distortion became noticeable. The MacIntosh amplifier clinic tested its distortion and found it to be about 20%! Replacing the tubes reduced the distortion for a month or two again...
  15. Audioguru

    A Welcome to EP For AudioGuru

    The "general purpose" 741 opamp is about 48 years old. I made a headphones amplifier with one about 45 years ago and it sounded awful. Modern audio opamps are much better.
  16. Audioguru

    A Welcome to EP For AudioGuru

    I say it like it is. I uploaded my avatar now.
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