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  1. Audioguru

    What is the proper way to use 1 cell lipo batteries in parallel?

    A BMS designed for a 12Ah battery will charge at 6A and a BMS designed for a 36Ah battery will charge at 18A. But your little solar panels cannot charge at such a high current anyway so either BMS will take weeks to charge the battery.
  2. Audioguru

    SuperCap Charging and Delivery System using Solar Panels

    A single Li-PO cell will explode then catch on fire if you try to charge it from 5V. You need a Lithium battery charging circuit that can be powered from 5V. The charging circuit limits the current and voltage properly and detects a full charge then disconnects the charging. A rechargeable...
  3. Audioguru

    Found this circuit on youtube

    Amazon does not know anything about electronic parts and probably does not even know which company made them. Most high power LEDs have a forward voltage range much more than you say, like from 10V to 14V. If you get one with a forward voltage of 10V and you power it with 12V then it explodes...
  4. Audioguru

    Found this circuit on youtube

    You and we need to see the datasheet for the 20W LED you have to see how they show to cool it and its actual range of forward voltage. If it already has current-limiting built-in then what is its range of current when the supply is 10V, 12V and 14V?
  5. Audioguru

    PWM motor noise getting into audio

    A piezo has an extremely high impedance so the high input impedance preamp picks up all kinds of interference. A piezo has a horrible frequency response making it a poor microphone. Why not use a normal electret microphone and a preamp with an input impedance of 10k to 20k instead? The electret...
  6. Audioguru

    Change output voltage and current of LED driver (Noob question)

    A page in the spec's shows a list of output many voltages and currents. They all calculate to almost 15W such as 12V at 1.2A (= 14.4W). Try it. Did the instructions show how to wire the different groups?
  7. Audioguru

    Charging a battery from well pump circuit (cycles on/off 120v)

    Your battery will never get charged since the charging power is only for very short time durations. Isn't it illegal to have low voltage wires in a conduit for the mains?
  8. Audioguru

    Charging a battery from well pump circuit (cycles on/off 120v)

    You never said how much current the light needs and for how long. A capacitor can hold enough charge to activate a charger for a few seconds but a battery needs hours to charge. I doubt that the well pump runs long enough to charge anything. How about using a fairly large windmill generator to...
  9. Audioguru

    SuperCap Charging and Delivery System using Solar Panels

    The voltage on a capacitor drops very quickly at the beginning of a discharge. Its voltage drops slowly when the charge is almost gone. The voltage on a battery drops slowly at the beginning and during a discharge until its charge is almost gone, then its voltage drops quickly. A voltage boost...
  10. Audioguru

    Will this work to increase running time of battery

    Converters work hard and produce some heat. The heat is wasted power from the battery. Does your 10W LED have something to limit its current? Please post a link to the datasheet of the LED.
  11. Audioguru

    SuperCap Charging and Delivery System using Solar Panels

    Capacitors in series do not equally share the voltage so one of them will have too much voltage and be destroyed.
  12. Audioguru

    Short-haul OTA TV rebroadcast?

    I have seen a thread where good TV signals are received on a broadband antenna and it is cabled to another antenna that is blocked by a hill or structure. Then the receiver's antenna receives the "re-transmitted" signal from the second antenna.
  13. Audioguru

    Short-haul OTA TV rebroadcast?

    Not many people simply watch one channel at a time. Instead they record another 3 or 4 channels at the same time. Then they are watching TV all the time and do not have time to go camping or anything else.
  14. Audioguru

    Short-haul OTA TV rebroadcast?

    Are you living in the RV because your wife kicked you out of the house?
  15. Audioguru

    zener voltage regulation

    The datasheet of an LM317 shows that its idle current is 5mA to 10mA all the time which is at least 10 times the current of an LCD clock. Its datasheet also shows that its input must be at least 1.5V higher than its output voltage when its load current is 20mA or less. All low-dropout voltage...
  16. Audioguru

    zener voltage regulation

    A capacitor is a poor choice to power anything because its voltage drops very quickly at the beginning of its discharge. A modern AAA alkaline or Lithium battery voltage drops very slowly for most of its discharge. Most clocks are powered for a long time from a replaceable battery. I have never...
  17. Audioguru

    zener voltage regulation

    5V through 100 ohms to a 3.3V Zener diode is a current of 95V - 3.3V)/100 ohms= 17mA. A load on the Zener diode will reduce its current. A 5W zener diode might have its voltage rated at 300mA or more. Post its part number and datasheet and look at them. I looked up a 5W 3.3V Zener diode and...
  18. Audioguru

    Is transistor faulty or something else amiss

    The transistor has nothing to do with the unsatisfying results of the horrible extremely simple circuit that worked but performed and sounded bad.
  19. Audioguru

    Switch for an audio jack with microphone.

    A speakerphone needs a transmit/receive manual switch or a voice-switching circuit to avoid acoustical feedback howling.
  20. Audioguru

    Is transistor faulty or something else amiss

    The law says you must not transmit a radio signal without a licence. The RF cops will catch you if you cause interference to somebody receiving a real radio station. The FM transmitters used for transmitting your MP3's to your car radio have a range of only 1m. Good luck.
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