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  1. Audioguru

    heated jacket power bank

    You did not consider the mAh rating of how long a battery can produce the 1.6A. A tiny lithium battery in a toy drone can supply 1.6A, but for maybe only a few minutes. It might be rated at 200mAh. A battery rated at 2Ah should produce 2A for 1 hour. The battery voltage boosting to 5V also uses...
  2. Audioguru

    Seeking a voice changer with mic and amplifier in order to communicate with hearing impaired

    My pretty bad high frequency hearing loss is normal for my age (73). I cannot hear many things said to me or the telephone or TV and radio without my hearing aids. But my hearing aids make my hearing normal again. The audiologist tried shifting down high frequencies but it sounded so weird that...
  3. Audioguru

    heated jacket power bank

    I watched a video on You Tube of tests of the cheap Chinese MT3608 module that looks like the AliExpress one. He bought 20 of them and 2 caught on fire and the remaining 18 did not work. I am glad that I did not tell you to put the module and batteries in your pocket for some extra warmth.
  4. Audioguru

    heated jacket power bank

    I do not know if the Li-PO batteries are name-brand or cheap fakes, new, old or used. They each might be able to produce 2.2A for 1 hour. 4 in parallel might be able to produce 8.8A for 1 hour. The datasheet for the MT3608 shows 93% efficiency when the current is low but about 85% at 1.6A...
  5. Audioguru

    heated jacket power bank

    Did you forget to calculate how many seconds the four 18650 Li-Ion cells can power the boost converter that heats the jacket? Have you ever tried a heated jacket that uses only 8W?
  6. Audioguru

    TPA3122D2 Class D Amp ticking sound and produces no music

    It is still a messy tangle of wires that are much too long. It should have neat short wires or a pcb.
  7. Audioguru

    Modifying 4.5 V (alkaline) lamp to run brighter with 3.6 V (NiMH)

    The thing was designed for only 4.5V. Why do you want to destroy it with a higher voltage? A higher voltage will cause a higher current which makes little electronic things smoke and burn. Right now I am modifying a similar product. It is a solar garden light that has a real IC and I have its...
  8. Audioguru

    Simple moisture meter circuit?

    EEK! I heard severe distortion on that You Tube video that I hate to hear. The guitar sounded much better with my hearing aids turned off. I think electric guitar players are deaf to that severe distortion.
  9. Audioguru

    Small low-power light sensor

    A few years ago, LDRs were used in solar garden lights. Most of mine failed and needed replacement, but the replacements also soon failed. Now solar garden lights do not use an LDR, instead they use the reliable glass solar panel instead. I think the cheap LDRs and cheap plastic solar panels get...
  10. Audioguru

    Beginner question : 555 timer pin 4

    Why does your stripboard use wires parallel with strips?? Then you cut those strips where they should not be cut.
  11. Audioguru

    what is the different between speaker wire and power wire

    It also happens with cars and with medicines. An expensive car is "better" than a cheaper car. The new expensive medicine a person is taking makes him feel better even when it is a fake sugar pill.
  12. Audioguru

    what is the different between speaker wire and power wire

    Cheap and expensive, every dynamic speaker has a low frequency resonance. The very low output impedance (0.08 ohms or less) of a modern amplifier damps that resonance if the cable resistance is less than a few ohms. If you have a mile or more of ordinary cable or very thin wires then the...
  13. Audioguru

    heated jacket power bank

    50,000mAh needs seventeen 18650 cells that certainly will not fit in it. A "polymer" (Li-PO) battery is usually flat but an 18650 Li-Ion battery is a cylinder. Will you buy this cheap kit without having any important details about which battery cells and how many?
  14. Audioguru

    TPA3122D2 Class D Amp ticking sound and produces no music

    Your problems are probably caused by your very messy tangle of wires. The parts should be close together and connected with short, straight wires. Buy the kit with its pcb instead. I agree that your input capacitors have backwards polarity, but since your tiny speakers (squeakers) produce no...
  15. Audioguru

    what is the different between speaker wire and power wire

    They make false claims (lies) about the very expensive "speaker wire" because some audiophools buy the stuff.
  16. Audioguru

    Amplifier the smartphone headphone port voltage

    He does not show which two pins of a 3-wires stereo plug he has the IR LEDs connected to and does not show a schematic to show if they are connected with opposite phase. No current-limiting resistor is shown so maybe they are already burned out.
  17. Audioguru

    Speaker power (wattage) and consumption

    You have a high power 12" woofer speaker that is 4 ohms and you have a 12V battery that produces only 13V. The datasheet shows that a Texas Instruments TPA3220 bridged stereo class-D amplifier IC powered from the battery produces max undistorted output power of only 18W per channel because the...
  18. Audioguru

    Beginner question : 555 timer pin 4

    Your schematic is a fuzzy Jpeg file type with its tiny parts so far apart that details like the circles with dots inside (diodes?) are not seen. A PNG file type is recommended since it makes extremely clear schematics. When you use LM317L ICs then the schematic should show it since the "L" has...
  19. Audioguru

    Amplifier the smartphone headphone port voltage

    The plug for the headphones has 3 connections but you do not show which 2 connections you used. The tip and ring are Left and Right channels and the sleeve is the ground for both channels. An LED works from DC current but the audio has no DC, it has AC. The single transistor amplifier I...
  20. Audioguru

    Amplifier the smartphone headphone port voltage

    If you have an external 5V power supply or battery then a single transistor can amplify the 3.5V to 5V.
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