Search results

  1. crutschow

    LiFePo4 100 AH battery charger

    Reminds me of someone else who posts on this forum. :rolleyes:
  2. crutschow

    LiFePo4 100 AH battery charger

    That's per cell of course. A 12V LiFePo4 battery has 4 cells.
  3. crutschow

    Replace power MOSFET in subwoofer plate amp, Sledge STA-1000D

    And where did you? MOSFET "saturation" is in the active or linear region, not fully on, which is in the ohmic region. For some odd reason this is different than a BJT where the saturation region is, of course, fully on.
  4. crutschow

    Combining two +12v car outputs

    What is the high and low beam current of the lamps?
  5. crutschow

    Combining two +12v car outputs

    The simplest way is to use a diode between the two wires (diode anode to high-beam wire). That will power the low-beam when the high-beam is on. The diode needs to be rated for the low beam current, and Schottky type diodes have the lowest voltage drop when conducting.
  6. crutschow

    Minimize Ripple in Rectifier by Waveform, Polarity, Bridge-Type, Inductor, Trafo?

    There a "swinging chokes" made for power supplies that have a high inductance an low currents, so the inductor doesn't "drop out" between half-cycles, which otherwise would increase the output ripple volage at those low currents.
  7. crutschow

    RCA Console Protection/DC Centering Mod

    100mV into an 8 ohm speaker generates only about 13mA of current, so that should not be a problem.
  8. crutschow

    Transformer overvoltage

    Here's a tracking preregulator using a high-voltage MOSFET and Zener, that will tolerate an output short.
  9. crutschow

    Transformer overvoltage

    One thing to be aware of is that the tracking regulator has near the full voltage across it in the event of an output short to ground.
  10. crutschow

    Electronics Knowledge and Skill Level of This Forum

    Yes. Electronic consumer repair is now mostly limited to factory warranty service, and that usually consists of replacing whole modules or circuit boards in the device, so not a lot of electronic knowledge is really needed for that.
  11. crutschow

    Electronics Knowledge and Skill Level of This Forum

    True, those kits are mainly just to assemble a useful device. Those kits I referenced are for learning, not making a permanent product. Look for advanced kits for adults or engineering students. But you remark about a "Throw away" society is a caution, since there is not a lot of electronic...
  12. crutschow

    Electronics Knowledge and Skill Level of This Forum

    John, if you want to start experimenting with electronics to learn, then you might start with one of the many electronic kits available for just that purpose.
  13. crutschow

    A Speaker OHM question

    There should be no problem in using 8 ohm speakers with the amp set to 6 ohms. The only difference may be a slightly lower maximum power into the 8 ohm speakers, but that's shouldn't an issue at normal listening levels.
  14. crutschow

    Alternating L/R 4-way flashers

    SPST has one contact the is normally open. (Normally is relay unenergized). SPDT has two contacts going to one wiper with one contact normally open and one normally closed.
  15. crutschow

    Alternating L/R 4-way flashers

    But the TS has been AWOL since Saturday, so perhaps this is all moot.
  16. crutschow

    Alternating L/R 4-way flashers

    Well, you are welcome to do that, but then all the lights would go on at the same time (Look at the the relay coil connections. It is de-energized when the flasher output is 12V). I did that so the common SPST vehicle relay could be used. True. The turn lamps would likely be isolated but the...
  17. crutschow

    Alternating L/R 4-way flashers

    Okay, so here's my take on a circuit to do that using one relay and four diodes for isolation: The diagram shows a SPDT relay but you can use a standard SPST vehicle relay. When the flasher is off, the small coil current goes through the low resistance of the unlit incandescent bulbs to energize...
  18. crutschow

    Timer Circuit design needed... Help !!!

    Below is the LTspice sim of a circuit using two 555 timers to do what you want: U1 is configured as an astable multivibrator that generates a 10s ON, 1s Off signal to the motor power relay U4 (green trace), and U3 is configured as a toggle flip-flop to flip the motor-field reverse relay U2 at...
  19. crutschow

    Timer Circuit design needed... Help !!!

    How do you reverse this brushed AC motor? Reversing the connections on an AC motor has no effect on its rotation direction.
  20. crutschow

    Can an audio amplifier be used to transmit or receive radio signals?

    No, your are not understanding the "facts". You need to broadcast an audio signal by modulating an RF carrier frequency. Broadcasting the signal directly as a radio wave would likely result an a signal too weak to detect, unless you had a transmitting and receiving antenna the was very large...
Top