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A relatively unimportant announcement...

Discussion in 'Electronic Design' started by Paul Burridge, Dec 24, 2003.

  1. James Meyer

    James Meyer Guest

    The simulation is unrealistic in another way too. The input signal
    generator with its 50 ohm internal impedance is coupled directly to the input
    transistor's base with a cap. That supplies the base with unreasonably high
    currents. In the real world where the antenna supplies current to the LC
    network, the relatively low input impedance will suck up all the current leaving
    precious little voltage at the input.

    Jim
     
  2. Fred Bloggs

    Fred Bloggs Guest

    He does in fact want a narrowband gain- how else is he going to
    discriminate which RF frequency is driving the meter?
     
  3. Gain BandWidth product. A common emitter amplifier has a gain
    bandwidth product. Lower the frequency (bandwidth) and you can have
    more gain. I found from experiment that a stage like you have been
    playing with has a gain bandwidth product of about 80 million. This
    allows a gain of 2 at 40 MHz.
     
  4. Not yet, John. I have to finish the real circuit.
     
  5. I delegate that to Kevin. I merely have to establish that the circuit
    works as advertised. ;-)
     
  6. In Paul Burridge typed:
    And to think I believed in you! (sob)
    ;-)
     
  7. Jim Thompson

    Jim Thompson Guest

    Your pomposity is under-whelming.

    You need to thoroughly study, AND understand, capacitors, diodes, and,
    from what I can see, I don't think you even understand resistors.

    And you're certainly IGNORANT about transistors.

    Have a good day ;-)

    ...Jim Thompson
     
  8. Thank you.
    I think it's a bit unreasonable accusing me of being *that* stupid.
    What precisely leads you to think I can't even understand resistors?
    There's a lot I still don't know, I fully ackowledge that.
    And the same to you.
     
  9. Jim Thompson

    Jim Thompson Guest

    Don't jump ahead. Enlighten me with some FUNDAMENTALS about
    capacitors and diodes. Then we'll fret over resistors.

    ...Jim Thompson
     
  10. Okay, I'm not sure if you're serious about this but I'll bite.
    Capacitors - ideal ones anyway - impede the flow of AC current in
    inverse proportion to their value for a a given frequency and block DC
    (except for a small leakage current). Diodes conduct mostly in one
    direction only when forwardly-biased after their energy hill/barrier
    height potential is overcome. Will that suffice for the sake of
    brevity? Your question wasn't very specific.
     
  11. Jim Thompson

    Jim Thompson Guest

    That will suffice... you actually defined *non-ideal* caps and diodes.

    NOW, why won't your capacitively-coupled rectifier produce the *DC*
    component of current which your meter needs to produce an indication?

    ...Jim Thompson
     
  12. Because the capacitor will block it, being in series with the diode
    and meter, ergo no DC to speak of through that part of the circuit.
    D'oh! I can't believe I came up with this hair-brained idea in the
    first place! :-( Thank God I don't have any reputation in the
    electronics field to lose. Happy now?
     
  13. Jim Thompson

    Jim Thompson Guest

    No, I would have rather you acted as a student in learning-mode
    instead of the belligerent stance you took.

    ...Jim Thompson
     
  14. I suppose the problem is I'm simply just not used to being wrong -
    except in this particular field where I manage an all-too-conspicuous
    degree of it.
    Can I go to bed now? I'm depressed. ;-)
     
  15. Jim Thompson

    Jim Thompson Guest

    Being wrong is something you have to get used to. I figure I've been
    wrong *at least* 10X the number of times I've been right. Engineering
    is about being able to wad up the piece of paper and start over...
    without being depressed.

    The only problem that ever caused me was the wife getting ticked
    because I just threw the paper wads over my shoulder into the dining
    room ;-)

    ...Jim Thompson
     
  16. Its a good thing your computer has a delete key. It would be
    hazardous for you to toss your computer across your shoulder. ;-)


    --
    Merry Christmas!

    Take care, and God bless.
    Michael A. Terrell
    Central Florida
     
  17. Bill Garber

    Bill Garber Guest

    message : Jim Thompson wrote:
    : >
    : > Being wrong is something you have to get used to. I figure
    I've been
    : > wrong *at least* 10X the number of times I've been right.
    Engineering
    : > is about being able to wad up the piece of paper and start
    over...
    : > without being depressed.
    : >
    : > The only problem that ever caused me was the wife getting
    ticked
    : > because I just threw the paper wads over my shoulder into the
    dining
    : > room ;-)
    : >
    : > ...Jim Thompson
    :
    : Its a good thing your computer has a delete key. It would be
    : hazardous for you to toss your computer across your shoulder.
    ;-)

    That's good point, Jim. Now please tell me what to
    do with this stack of schematics I have drawn and
    never got around to doing anything with yet. There
    must be 3-4 dozen of them from simple LED flashers
    to full blown interfaces. ;-)

    Bill @ GarberStreet Enterprizez };-)
    Web Site - http://garberstreet.netfirms.com
    Email -
    Remove - SPAM and X to contact me
     
  18. Mark Jones

    Mark Jones Guest

    In news: (Bill Garber):

    You could always post them here, using some obscure title like "STD's" or
    something. :)
     
  19. Bill Garber

    Bill Garber Guest

    "Mark Jones" <127.0.0.1> wrote in message
    : In (Bill Garber):
    : > message : >> Jim Thompson wrote:
    : >>>
    : >>> Being wrong is something you have to get used to. I figure
    I've been
    : >>> wrong *at least* 10X the number of times I've been right.
    Engineering
    : >>> is about being able to wad up the piece of paper and start
    over...
    : >>> without being depressed.
    : >>>
    : >>> The only problem that ever caused me was the wife getting
    ticked
    : >>> because I just threw the paper wads over my shoulder into
    the dining
    : >>> room ;-)
    : >>>
    : >>> ...Jim Thompson
    : >>
    : >> Its a good thing your computer has a delete key. It would
    be
    : >> hazardous for you to toss your computer across your
    shoulder. ;-)
    : >
    : > That's good point, Jim. Now please tell me what to
    : > do with this stack of schematics I have drawn and
    : > never got around to doing anything with yet. There
    : > must be 3-4 dozen of them from simple LED flashers
    : > to full blown interfaces. ;-)
    : >
    : > Bill @ GarberStreet Enterprizez };-)
    :
    :
    : You could always post them here, using some obscure title like
    "STD's" or
    : something. :)

    I could do that. How many of you guys have Apple IIs? ;-)
    Quite a few of them are for those.

    Bill @ GarberStreet Enterprizez };-)
    Web Site - http://garberstreet.netfirms.com
    Email -
    Remove - SPAM and X to contact me
     
  20. Jim Thompson

    Jim Thompson Guest

    I have a *very* large hard-drive on my simulation machine ;-)

    ...Jim Thompson
     
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