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  1. crutschow

    Vacuum Tubes (Valves)

    There are hundreds of satellites in orbit, all with large amounts of semiconductor circuits (no tubes) and they readily survive those CMEs. I worked on a military satellite with solid-state electronics that was designed to withstand the EMP from a nuclear blast in space, well above what any CME...
  2. crutschow

    Bose Wave 1 - AWRC-1G - Treble & Bass Adjustments - Too Much Bass

    And how is that pertinent to solving the problem?
  3. crutschow

    Bose Wave 1 - AWRC-1G - Treble & Bass Adjustments - Too Much Bass

    The intent of the cotton is not to change the resonant frequency, which could eliminate desired bass frequencies, but to dampen (muffle, attenuate) the sound by the friction of the sound going through the cotton, just like cotton does in your ears. You may have to pack it in there somewhat...
  4. crutschow

    Bose Wave 1 - AWRC-1G - Treble & Bass Adjustments - Too Much Bass

    Okay, DP's post gives me an alternate idea. Instead of trying to change the tube, which I think is plastic, just put cotton balls in it to damp the bass. Adjust number of cotton balls to taste.
  5. crutschow

    110 220V detection

    You could use a 220Vac coil relay with the NC contacts connecting the 110V heaters, and the NO contacts to the 220V heaters. It would not energize for a 110V input, but would for 220V to connect the proper heaters. (I assume the 220V heater could just be two 110V heaters in series.)
  6. crutschow

    Year 2038 problem.

    There was also a concern about the year 2000 being a big problem for computers, but that turned out to be nothing of significance. The 2038 problem will likely be handled similarly.
  7. crutschow

    Bose Wave 1 - AWRC-1G - Treble & Bass Adjustments - Too Much Bass

    The capacitors can also be non-polarized speaker crossover capacitors such as these from Parts Express:
  8. crutschow

    Bose Wave 1 - AWRC-1G - Treble & Bass Adjustments - Too Much Bass

    Likely no adjustment anywhere. The only thing I can think of is to put a large non-polarized capacitor (for example, two electrolytics back-to-back) in series with the speaker leads. Start with about 500µF and go down from there to reduce the bass.
  9. crutschow

    Vacuum Tubes (Valves)

    I believe they are still used for high power radio transmitters. Some audiophile nuts like the "better" sound of tube amps (whatever better is), but you can't beat a high-end solid-state amp for generating a pure, low distortion signal. If you ever go to an audio show you are unlikely to find...
  10. crutschow

    Help adding audio out to a TV

    Tapping off the speaker signals could be problematic, since the could be not-grounded, bridge-output signals. You might try just disconnecting the internal speakers and connecting the wires to two external, full-range speakers and see if that's sufficient. If not, then we can go from there.
  11. crutschow

    Cable voltage drop - capacitor reservoir

    It depends upon the amount of capacitance needed to handle the current transient. A super capacitor is just an electrolytic capacitor designed to have a very high capacitance.
  12. crutschow

    Turn On and Off a Smaller Voltage from a Larger One

    Still need to know the current in the 1.75V circuit.
  13. crutschow

    Turn On and Off a Smaller Voltage from a Larger One

    What is the load for the 1.75V signal?
  14. crutschow

    How to safely short the leads of a DC motor together with no power is applied.

    Should work.
  15. crutschow

    How to safely short the leads of a DC motor together with no power is applied.

    The starting current for a motor can be several times its rated power (mainly determined by its winding resistance), but that relay will probably handle it. You can measure the motor resistance with an ohmmeter to get an idea of the actual starting current. (Be sure to subtract the ohmmeter...
  16. crutschow

    How to safely short the leads of a DC motor together with no power is applied.

    That's an 85A rated unit. I thought you wanted 100A? As Minder's schematic shows, it is a DPST (alternate poles on). It has 6 terminals but not 6 poles (as defined by relay convention "The pole of a relay is the terminal common to every path. Each position where the pole can connect is called...
  17. crutschow

    How to safely short the leads of a DC motor together with no power is applied.

    The COM terminal goes to the motor, the N.O. terminal goes to the power supply, and the N.C. terminal goes to ground/common. The motor then receives the supply voltage when the relay coil as powered, and is grounded when the relay coil is not powered.
  18. crutschow

    How to safely short the leads of a DC motor together with no power is applied.

    Perhaps one of these 100A SPDT relays would work. Edit: Here's a solenoid type that looks more robust.
  19. crutschow

    Simple 555 Timer

    Why is that a problem? Is the power not applied continuously to the circuit? Try connecting the positive side of C2 to the V+ supply, and the negative side to pin 6 and R3. Also change R1 back to 10kΩ. R3 is not needed--you can connect pins 6 and 7 together. With that the 555 should power up...
  20. crutschow

    Simple 555 Timer

    What is a "staircase timer"? What is the purpose of the 555? What exactly do you want the circuit to do?
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