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  1. Audioguru

    Huming sound in homemade bluetooth speaker

    Your amplifier shows a fairly old IC made by Tripath. Nobody knows who makes the cheap Chinese amplifier. Tripath went bankrupt some years ago, maybe because their amplifier ICs did not work properly.
  2. Audioguru

    Inter M Qd 4960 Amplifier Problem

    We call it a sub-woofer, not a taxi cab (made of brass?). The bridged amplifier produces 480 Watts into 8 ohms. Maybe your taxi cab was 4 ohms then the current was double the maximum allowed current.
  3. Audioguru

    Headset

    I looked at the specifications of very expensive Senheiser headphones and they are also missing the important details.
  4. Audioguru

    Headset

    The technical data in the product sheet is completely worthless because the important details are missing. Frequency response is when the devise responds to different frequencies. But the spec's say that it responds to ALL audible frequencies. That is not how a frequency response is supposed to...
  5. Audioguru

    Two seven segment displays

    The assessment is looking for somebody who understands very old TTL logic ICs and can show a simple circuit assembled to do what is clearly asked for. It seems that you have no education or experience to do it. If somebody here does it for you and you just copy it then you do not meet the...
  6. Audioguru

    Dryer's heat fluctuates?

    I have never seen or got bitten by a bed bug. I have never been to a ghetto.
  7. Audioguru

    Auto Off Adaptor

    Read about lithium batteries. The charger circuit must detect a full charge then shut off. The "charger" for your phone is simply a dumb power supply for the smart charging circuit that is inside your phone.
  8. Audioguru

    Dryer's heat fluctuates?

    The amount of moisture in the clothes and humidity in the air varies, which affect the heat of the clothes after a fixed time. My clothes dryer does not simply have a timer like some cheap ones. instead it measures the humidity of the air in the dryer and stops when the humidity becomes fairly...
  9. Audioguru

    Need help With Limiting Voltage For Lights

    The JVC subwoofer amplifiers have maximum average output voltage of 28V with peaks at 40V. The LED strips use 12V. If you connect two LED strips in series then they will operate on 24V and use a full-wave rectifier bridge module to convert the audio AC to DC. Do not connect a capacitor and do...
  10. Audioguru

    Need help With Limiting Voltage For Lights

    You seem to be designing an LED and capacitor destroyer instead of collecting important spec's and making a few simple calculations. 1) Please post the datasheet for the 12V LEDs so we can see the value of the built-in resistor that limits the current. 2) Please post the manufacturer's name and...
  11. Audioguru

    Need help With Limiting Voltage For Lights

    A hIgher capacitor value (two same value capacitors in parallel) have double the capacitance of one capacitor. Then they pass lower frequencies and have less loss at low frequencies which will make the LEDs brighter. Most electrolytic capacitors have a + wire and a - wire and should not be used...
  12. Audioguru

    Need help With Limiting Voltage For Lights

    The speaker output from an audio amplifier produces AC that might destroy LEDs that use DC (the D in "LED" is a diode). An LED is from 1.7V to 3.5V so maybe yours have a few LEDs in series or have a resistor in series to limit the current. The amount of output power from the amplifier determines...
  13. Audioguru

    Soldering iron trouble.

    I think the blue color of the soldering iron shaft shows that it is way too hot and it incinerates the flux in the solder and makes the solder and tip oxidize very quickly. I think a cheap ebay soldering iron "with adjustable temperature" simply has a light dimmer to adjust the temperature but...
  14. Audioguru

    Need recommendation for rheostat or potentiometer

    When you power up the motor then you should measure the voltage from the battery at the same time. Your battery might be too old to provide the extremely high starting current without its voltage dropping very low. The wiring must also pass the extremely high current without dropping the voltage.
  15. Audioguru

    Microphone

    Ask Plantronics or look on their website, they make the thing. TigerDirect know nothing about it except how much profit they make when they sell it. An electret mic is a condenser mic with the 48V stored in the electret material and there is a Jfet impedance converter inside that needs to be...
  16. Audioguru

    LED VU/PPM-meters -metering scales and their use

    +3dB sounds only a littler louder, +6dB is again a little louder than +3dB. +6dB is a voltage gain of 2. Must people think that an amber or yellow light is a warning (here it might warn that distortion is beginning to happen at this level and red might mean that severe distortion is happening...
  17. Audioguru

    Red Green Led 2 Leg

    3.3V is probably the green forward voltage and the red will be about 1.8V to 2.2V. Use a single resistor to ground that is (12V - 1.8V)/20mA= 510 ohms or more. The resistor will dissipate (heat) with 0.2W so use a half-watt resistor.
  18. Audioguru

    Mosfets in parallel

    They must be matched or the more sensitive one will do all the work and maybe burn out.
  19. Audioguru

    LED HOW TO?

    8x8=64 LEDs. If each LED uses 20mA then the poor battery will die quickly trying to produce 1280mA. An ordinary little 9V battery cannot produce such a high current. Three LEDs in series will not light for long from a 9v battery but strings of two LEDs in series and each string with a series...
  20. Audioguru

    Need help building a circuit for low voltage alarm with bi color LED with flasher

    Your bi-color LED is called "common anode", not PNP.
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