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#1
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Richard Clark wrote:
Cecil Moore wrote: It just occurred to me that you and I may be talking about two different phases. After weeks of this being explicitly stated by very many critics, it just occurred to you? If it was ever stated, I missed it. I suspect it was never stated and some people jumped to false conclusions. I don't think anyone is stupid enough to assert that the phase shift in a capacitor is the same as it is in the absence of any physical impedance discontinuity. -- 73, Cecil http://www.w5dxp.com |
#2
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On Sun, 16 Dec 2007 19:12:50 GMT, Cecil Moore
wrote: I don't think anyone is stupid enough to assert that the phase shift in a capacitor is the same as it is in the absence of any physical impedance discontinuity. Capacitance is not obtained in a physical impedance discontinuity? or is it: Physical impedance discontinuity is not obtained from a capacitor? or is it: Could be either is inside a box, supplying only the terminals to either; specifically either of which is indeterminate at a single frequency where the terminals might present 43.4 degrees? (or any suitable angle) There are any number of stupid choices available. The question is: Has your netzheimers progressed so far as to add another one? At 800 postings, the odds must be distinctly favoring stupid. Make it the daily-double: Does a stupid math error make the answer valid? |
#3
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Richard Clark wrote:
Cecil Moore wrote: I don't think anyone is stupid enough to assert that the phase shift in a capacitor is the same as it is in the absence of any physical impedance discontinuity. Capacitance is not obtained in a physical impedance discontinuity? or is it: You missed the point. A terminating capacitor is a two terminal network. The point where two pieces of feedline are connected is a four-terminal network. A two-terminal network is different from a four-terminal network. -- 73, Cecil http://www.w5dxp.com |
#4
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On Sun, 16 Dec 2007 16:11:05 -0600, Cecil Moore
wrote: Richard Clark wrote: Cecil Moore wrote: I don't think anyone is stupid enough to assert that the phase shift in a capacitor is the same as it is in the absence of any physical impedance discontinuity. Capacitance is not obtained in a physical impedance discontinuity? or is it: You missed the point. A terminating capacitor is a two terminal network. The point where two pieces of feedline are connected is a four-terminal network. A two-terminal network is different from a four-terminal network. More signs of your confusion. How would you know how many terminals if its inside a box? |
#5
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Richard Clark wrote:
Cecil Moore You missed the point. A terminating capacitor is a two terminal network. The point where two pieces of feedline are connected is a four-terminal network. A two-terminal network is different from a four-terminal network. More signs of your confusion. How would you know how many terminals if its inside a box? If you were locked in a black box, you would be ignorant of night and day. Does that mean that night and day would not be happening? Hint: No, it would just mean you are ignorant. Your ignorance changes absolutely nothing outside of the box in which you are locked. Why does my ignorance of what's in the black box change the reality of what's in the black box? Hint: it doesn't. The fact that I am ignorant of the four terminal network in the box doesn't change the fact that it is a four terminal network. The fact that you won't allow me to open the box and measure the phase shift at the impedance discontinuity doesn't change the fact that it is 36.6 degrees. -- 73, Cecil http://www.w5dxp.com |
#6
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On Mon, 17 Dec 2007 15:22:44 GMT, Cecil Moore
wrote: Richard Clark wrote: Cecil Moore You missed the point. A terminating capacitor is a two terminal network. The point where two pieces of feedline are connected is a four-terminal network. A two-terminal network is different from a four-terminal network. More signs of your confusion. How would you know how many terminals if its inside a box? If you were locked in a black box, you would be ignorant of night and day. Does that mean that night and day would not be happening? Hint: No, it would just mean you are ignorant. Your ignorance changes absolutely nothing outside of the box in which you are locked. Why does my ignorance of what's in the black box change the reality of what's in the black box? Hint: it doesn't. The fact that I am ignorant of the four terminal network in the box doesn't change the fact that it is a four terminal network. The fact that you won't allow me to open the box and measure the phase shift at the impedance discontinuity doesn't change the fact that it is 36.6 degrees. OK, So you are ignorant of what is inside the box. Rather a long ramble to such a simple conclusion. Are you still ignorant of which of two phases? Your rambling confusion has yet to come to terms even to the point of not being able to name both of them in one posting! Like trying to wake a sleep-walker, I hesitate to offer a dangerous suggestion with you in your condition: Could they be "phase" shift and "phase" length? In your somnambulant state of foggy recall It just occurred to me that you and I may be talking about two different phases. can you tell the group what the two different phases are? This could be an important moment in recovery (it may take only 11 steps more). Take your time, we appreciate that your sudden catharsis can jog your mind into curious responses...even though they would be indifferentiable from the several hundred that preceded. ;-) |
#7
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Richard Clark wrote:
Are you still ignorant of which of two phases? I have spelled out the desired phases three times now. This will be the forth time. --43.4 deg 600 ohm line--+--10 deg 100 ohm line--open Vfor1--|--Vfor2 The phase shift we are looking for is between Vfor1 and Vfor2. I might as well perform the calculations for you since you seen to be incapable of doing so. If we assume a reference of 100 volts at zero degrees incident upon the open end of the stub, then back at the impedance discontinuity: Vfor2 = 100 volts at -10 deg. Vfor1 = 143.33 volts at -46.6 deg The phase shift between Vfor1 and Vfor2 is 36.6 degrees just as it has to be for a 90 degree phase shift to occur end to end in the above 1/4WL stub. Vref2 = 100 volts at 10 deg Vref1 = 143.33 volts at 46.6 deg -- 73, Cecil http://www.w5dxp.com |
#8
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Cecil Moore wrote:
Richard Clark wrote: Cecil Moore wrote: I don't think anyone is stupid enough to assert that the phase shift in a capacitor is the same as it is in the absence of any physical impedance discontinuity. Capacitance is not obtained in a physical impedance discontinuity? or is it: You missed the point. A terminating capacitor is a two terminal network. The point where two pieces of feedline are connected is a four-terminal network. A two-terminal network is different from a four-terminal network. Cecil, This appears to be an unusual definition. How does the "point where two pieces of feedline are connected" become a four-terminal network? One typically thinks of a four-terminal network as having inputs and outputs, with something between. What is that "something between" in the case of two connected feedlines? In your models this "something" seems to have no dimensions and no characteristics other than a phase shift. Are you suggesting that every simple connection is now a four-terminal network? Do all of the textbooks need to be re-written? 73, Gene W4SZ |
#9
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Gene Fuller wrote:
Cecil Moore wrote: You missed the point. A terminating capacitor is a two terminal network. The point where two pieces of feedline are connected is a four-terminal network. A two-terminal network is different from a four-terminal network. This appears to be an unusual definition. Not unusual at all, Gene. The two input terminals to the black box are on one side. The two output terminals from the black box are on the other side. The impedance discontinuity is inside the box. The black box is extremely small. Give me the four s-parameters, s11, s12, s21, and s22 and I can tell you virtually everything about what is inside the black box without even applying a signal. -- 73, Cecil http://www.w5dxp.com |
#10
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Cecil Moore wrote:
Gene Fuller wrote: Cecil Moore wrote: You missed the point. A terminating capacitor is a two terminal network. The point where two pieces of feedline are connected is a four-terminal network. A two-terminal network is different from a four-terminal network. This appears to be an unusual definition. Not unusual at all, Gene. The two input terminals to the black box are on one side. The two output terminals from the black box are on the other side. The impedance discontinuity is inside the box. The black box is extremely small. Give me the four s-parameters, s11, s12, s21, and s22 and I can tell you virtually everything about what is inside the black box without even applying a signal. BZZZT! Wrong answer. Nobody ever said anything about the "other side" of the black box. Everything has been referenced to "the point where two pieces of feedline are connected." Nobody is trying to suggest that what is inside one black box is identical to what is inside another black box. The only thing known is that the *two* accessible terminals to each of the black boxes show the same specific impedance at the given frequency. Nothing else. Yet by your models and math the black boxes don't behave the same in your test circuit. You still have not addressed the original question posed by Keith. 73, Gene W4SZ |
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