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I've always wondered and never found the answer...

Discussion in 'Ham Radio Discussions' started by VE3GZB, Jul 7, 2018.

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  1. VE3GZB

    VE3GZB Ham Member QRZ Page

    What smart cookie looked at a transmission line and invented the SWR meter?

    It seems like a pretty clever invention, yet it's not entirely intuitive by just looking at a section of transmission line.

    73s VE3GZB
     
    N9CAV likes this.
  2. SM0AOM

    SM0AOM Ham Member QRZ Page

    The directional coupler was a pre-war invention, made by engineers on both sides of the Atlantic. One prominent contributor was Dr. Werner Buschbeck at Telefunken in Germany.

    During WW2 it came into use for many applications in microwave and radar engineering, but not always in the forms that we recognise today.

    Post-war, the directional coupler was made popular by Korman, Jones and Sontheimer, who devised the "Micromatch", and by Norgaard et al at the NRL who described the coupled line directional coupler now known at the "Monimatch".

    Both the Micromatch and the Monimatch work according to the bridge principle, the original Micromatch was a Wheatstone bridge, and the Monimatch a Maxwell bridge.

    In the 1950s there became a need for frequency-independent SWR meters, and the Buschbeck coupler was "re-invented" by using toroid transformers by people such as Warren Bruene W0TTK, head of transmitter engineering at Collins. Other contributors made similar designs.

    In the meantime, a development of the Monimatch became the nucleus of the Bird Thruline wattmeter, which accomplishes some frequency independence by the use of capacitive loading of the coupler output voltage before detection.

    The Buschbeck and Bruene couplers were further developed into the "Tandem Match" using both voltage and current sensing transformers, which has become a very common coupler in our time.


    73/
    Karl-Arne
    SM0AOM
     
    KA0USE, KD0CAC, W5INC and 3 others like this.
  3. W4NNF

    W4NNF XML Subscriber QRZ Page


    Yep, smart cookie.

    Though to tell you the truth, many hams didn't own or need an SWR meter back in the day of vacuum tubes. Many, maybe most of us average slobs, were using at least close-to-resonant wire antennas that were easily tuned by adjusting the transmitter's LC circuit. Dip the plate and peak the grid and you were on your way. You would have a feel for the indications you should get in tuning and would know when something went awry.
     
  4. K1OIK

    K1OIK Platinum Subscriber Platinum Subscriber QRZ Page

    From OH2FFY:

    "In all honesty is one of many common phrases that people use in order to appear more honest and trustworthy.
    Usually used when it comes to selling something that's you wouldn't really want to own.
    In all honesty , what looks like swamp reeds , is actually a natural wild grass land.
    or
    To be completely honest , an old woman only drove this to church on Sundays.
    When I hear someone trying to convince me that they are honest , I look for the catch.
    There are honest people out there , but they don't need to convince you of it"
     
  5. WZ7U

    WZ7U Ham Member QRZ Page

    Really
     
  6. AB8MA

    AB8MA Premium Subscriber QRZ Page

    To tell you the truth, I have no idea what you are trying to tell us all here. We are all honestly flummoxed.
     
  7. WZ7U

    WZ7U Ham Member QRZ Page

    More virtue signalling
     
  8. W4ZD

    W4ZD Ham Member QRZ Page

    Reading the past few postings, I conclude, hams are strange. Could it be from inhaling the fumes of overheated ICs? Maybe I should cover up the fan vents on my rig. :p
     
    N4FZ likes this.
  9. KD2NOM

    KD2NOM XML Subscriber QRZ Page

    Why do you do this Burt?

    Seriously. Why?
     
    N1DQQ and W7UUU like this.
  10. G0JUR

    G0JUR Ham Member QRZ Page

    Just because.
     
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