Search:

Type: Posts; User: BradtheRad

Page 1 of 20 1 2 3 4

Search: Search took 0.10 seconds.

  1. Closed: Re: Microwave signal transmission: shortest path or shortest time?

    It seems more likely that brain tissue absorbs microwaves rather than reflect them back toward the source.
    However perhaps bone tissue might reflect them.

    Ultrasound reflects from internal...
  2. Closed: Re: Voltage sense using summing amplifier

    You don't say it's mandatory to use the math oriented analytical approach... but one trick you can try is to substitute a potentiometer for Rf1 & Rf2. This gives you a vast adjustable range of gain...
  3. Closed: Re: Overloaded fuse/broken pin issue- PARTS RESOURCE NEEDED

    * Instruction manual: the section about fuses tells of the importance of setting the machine for 120VAC or 240VAC.

    * About capacitors, examine electrolytic (especially the largest ones) for signs...
  4. Replies
    3
    Views
    260

    Closed: Re: Engineer Finger Test

    No doubt capacitance plays a part but in addition our body is an antenna which picks up RF (and/or mains hum). Then in some way, shape, manner or form, we affect an adjacent circuit.

    Instruments...
  5. Closed: Re: Overloaded fuse/broken pin issue- PARTS RESOURCE NEEDED

    It seems like it's almost the rule, that people don't get rid rid of working equipment until it develops a problem, then they unload it on someone like you and me.

    * Your photograph shows more...
  6. Closed: Re: Adding a 3 band equalizer to a phantom powered electret mic amp

    When a mic produces 10 or 100mV amplitude it's wise to send it to a pre-amp right away so your desired signal stays dominant over any added noise further on.

    Your link is to Rod Elliott's site...
  7. Replies
    14
    Views
    612

    Closed: Re: would an engineer use this equation?

    Links to tables of wire gauges showing specs and safe ampere-carrying capacity. There is a difference as to whether the wire is in open air, or bundled on an inductor.
    ...
  8. Closed: Re: Questions of mechanical to electrical energy transfer

    Bicycle mount generator via internet search. Often a headlamp is included (for more money).
    At left is the contact wheel which spins against the tire.

    157912

    For comparison, cheap battery...
  9. Closed: Re: Questions of mechanical to electrical energy transfer

    This is similar to two AAA in series. Mine have instructions to charge at 72mA overnight.

    There are store-bought generators which you mount close to the tire. It's on a spring-hinge. Inside is a...
  10. Replies
    4
    Views
    289

    Closed: Re: Smps design with UC3844 for 300V /0.5A

    Although it's feasible to use smps method to convert mains AC (assuming 230V) to 300 VDC...
    I can't help but think there's a simpler topology. It looks as though C6 acquires 330 VDC peak. C6...
  11. Replies
    16
    Views
    637

    Closed: Re: impedance of antenna

    To my limited understanding a tuning circuit is usually present. This is true whether you're transmitting or receiving. If transmitting then you want resonant action, resulting in standing waves....
  12. Replies
    3
    Views
    341

    Closed: Re: soldering with silver content

    I have silver solder in wire form. It's stronger than normal tin/lead solder.
    Silver type is useful to fix metal parts where the fix should be done quickly and occupy a small area. The aim is to...
  13. Replies
    16
    Views
    637

    Closed: Re: impedance of antenna

    Impedance of 50 ohms is a spec which is associated with voltage and current levels. Suppose the antenna generates a 50 µV signal... Then it implies you can expect 1 µA to flow.

    It tells you what...
  14. Closed: Re: Gas flow meter + Gas pressure meter + Vacuum meter?

    Pressure of 1 kPa barely moves the needle on an everyday automotive vacuum gauge. This low pressure might be detected by the depth of liquid a hose is immersed and still allow gas to flow. The liquid...
  15. Replies
    3
    Views
    318

    Closed: Re: Filter topology anyone knows

    It looks as though mains AC comes in at left. And I think it filters power to an appliance at right. I'm reminded of a store-bought 'noise filter' which I took apart. It claimed to improve radio and...
  16. Closed: Re: Different current measurmen numbers on a FLUKE 289

    My meters are the same. Each mA range contains a different shunt resistance.

    When current level is unknown I start with the highest mA range to take a reading. If the meter moves a tiny distance...
  17. Closed: Re: Laptop RAM upgrade (new RAM doesn't work in RVS slot, but works in STD slot)

    Quickly after you turn on the computer you should see a notice to press F2 (or F10 or 'delete' or some other key or combination of keys) to enter the BIOS listing. If you press the correct key soon...
  18. Closed: Re: how to generate 4MHz clock from 2 MHz clock.

    This simple frequency doubler turns up via internet search. XOR (exclusive-OR) gate turns on at upward and downward transitions. RC values are not critical.

    157820
  19. Replies
    1
    Views
    231

    Closed: Re: Problem with the output of the switch

    I suspect the output ought to have some amount of resistive load on it, to allow charging and discharging in the capacitors.
  20. Closed: Re: How to analysis the loading effect of this kind of circuit?

    The 150 ohm resistance is always in the path between the op amps, thus it is the ohmic portion of the load.

    As for capacitors, they present zero resistance for a brief time after a change in...
  21. Replies
    2
    Views
    298

    [PIC]Closed: Re: PIC Program for Multilevel Inverter

    Your timing scheme has 14 steps. Create 7 arrays named SW1(), SW2(), etc.
    In each array create 14 elements which contain the successive state (0 or 1) of that switch.

    Go through a for-next loop...
  22. [SOLVED]Closed: Re: Ultra low-power timer to make a power saving circuit

    A store-bought appliance timer could be adapted to suit your purpose.

    To build your own long-period timing circuit there is the 4060 IC (or its cousin 4040 or 4020). It consists of a series of...
  23. Closed: Re: Power Supply Design for timer application

    There is the optoisolator (optocoupler) method for monitoring voltage. Create expanded scale readings by installing a zener diode inline.

    157778
  24. Closed: Re: Basic 12v Battery VOLTAGE METER, more resolution needed

    Congratulations on getting your project to work. Since you're in bargraph mode there can be 1/2 or 1 watt going through the safety resistor. That is so warm you can't hold it between your fingers.
    ...
  25. Closed: Re: Glow LED on specified counter values 0-500 in 89c52 uC

    It looks as though you light led1 every 15 counts starting at 10.
    Likewise led2 lights every 15 counts starting at 15.

    This can be done by a simple formula, for each led.
Results 1 to 25 of 500
Page 1 of 20 1 2 3 4