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Roy Lewallen wrote: Wes Stewart wrote: It operated a lot better than "Dr." (not so) Slick does. He makes a comment that no one here builds amps. I present evidence to the contrary and this is the best he can do. A bunch of pictures of dubious origin... Would you care to give us some of your design notes? Or did you build this one from someone elses schematic? I think Garvin Yee ("Dr. Slick") has WALG (Worked All Los Gatos) and maybe even WAB (Worked All Berkeley). Does that count? Roy Lewallen, W7EL It certainly does count. I have also WYM (Worked Yo' Momma!) Slick |
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wrote in message oups.com... Roy Lewallen wrote: Wes Stewart wrote: It operated a lot better than "Dr." (not so) Slick does. He makes a comment that no one here builds amps. I present evidence to the contrary and this is the best he can do. A bunch of pictures of dubious origin... Would you care to give us some of your design notes? Or did you build this one from someone elses schematic? I think Garvin Yee ("Dr. Slick") has WALG (Worked All Los Gatos) and maybe even WAB (Worked All Berkeley). Does that count? Roy Lewallen, W7EL It certainly does count. I have also WYM (Worked Yo' Momma!) Slick Garvin There is a flaw in your reasoning. In order for somebody to copy an amp, or whatever, somebody else still had to design and write up the original. In many cases, you are here talking to that "somebody else". Tam/WB2TT |
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Wes Stewart wrote: Read the text, Bozo. And then repeat after me: Rho can be greater than one, rho can be greater than one, rho can be greater than one.... Repeat after me, Dweeb-head: Only with Return Gain, Only with Return Gain, Only with Return Gain..... Now, now, boys, be nice. Both of you can be right if you are not talking about *power* gain. Since you are discussing VSWR, rho can be greater than one AND the voltage return gain can be greater than one. The voltage across a resonant circuit depends upon the 'Q' and can certainly be higher than the applied incident voltage. For that exact same reason, Vref can be higher than Vfor. It occurs when the load is the conjugate of Z0 and Z0 is not purely resistive. -- 73, Cecil http://www.qsl.net/w5dxp |
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wrote: Wes Stewart wrote: Read the text, Bozo. And then repeat after me: Rho can be greater than one, rho can be greater than one, rho can be greater than one.... Repeat after me, Dweeb-head: Only with Return Gain, Only with Return Gain, Only with Return Gain..... Now, now, boys, be nice. Both of you can be right if you are not talking about *power* gain. Since you are discussing VSWR, rho can be greater than one AND the voltage return gain can be greater than one. The voltage across a resonant circuit depends upon the 'Q' and can certainly be higher than the applied incident voltage. For that exact same reason, Vref can be higher than Vfor. It occurs when the load is the conjugate of Z0 and Z0 is not purely resistive. -- 73, Cecil http://www.qsl.net/w5dxp Given a 396 meter length of Radio Shack RG58. At 250 kiloherz TLD says (after some manipulation) that it has a propagation constant of 689.6 X 10^-9 + j7.933 X 10^-3. Zo is 50 -j4.344. Feed it with a voltage source of 100 volts with a source resistance of 50 ohms. Put a load on it of j50 ohms. The voltage reflection coefficient at the load is -4.116 X 10^-3 + j1.091. The absolute value of this number is 1.091, a number greater than one. The power into this line is .1088 Watts. Fine. However, if I calculate the power at the middle of the line, I get -34.42 watts, a negative number. Moreover, the SWR calculated at the beginning of the line is -23.21. What is negative average power? What does a negative SWR signify? 73, Tom Donaly, KA6RUH |
Tom Donaly wrote:
Given a 396 meter length of Radio Shack RG58. At 250 kiloherz TLD says (after some manipulation) that it has a propagation constant of 689.6 X 10^-9 + j7.933 X 10^-3. Zo is 50 -j4.344. Feed it with a Doesn't that imply that the the matched line loss at 0.25MHz is 689.6E-9*20*e^1*100 dB/100m? That is 0.0006dB/100m, it seems too good to be true! Owen |
Owen wrote:
Tom Donaly wrote: Given a 396 meter length of Radio Shack RG58. At 250 kiloherz TLD says (after some manipulation) that it has a propagation constant of 689.6 X 10^-9 + j7.933 X 10^-3. Zo is 50 -j4.344. Feed it with a Doesn't that imply that the the matched line loss at 0.25MHz is 689.6E-9*20*e^1*100 dB/100m? That is 0.0006dB/100m, it seems too good to be true! Owen Hi Owen, It is too good to be true. (Just consider it came from an unusually good batch.) The whole exercise is nonsensical, though, because it results in negative power and a negative SWR. Increase the loss to a more realistic value and the negative power goes away as does the negative SWR while the absolute value of the reflection coefficient is still greater than 1. I was hoping I could get some kind of nut philosophical justification for negative average power out of Cecil, but you sprang the trap. 73, Tom Donaly, KA6RUH |
Tom Donaly wrote:
I was hoping I could get some kind of nut philosophical justification for negative average power out of Cecil, but you sprang the trap. The sign of power can indicate direction as in: Pnet = Pfor - Pref or destructive interference as in: Pnet = P1 + P2 - 2*SQRT(P1*P2) -- 73, Cecil http://www.qsl.net/w5dxp |
CAM wrote:
Tom Donaly wrote: I was hoping I could get some kind of nut philosophical justification for negative average power out of Cecil, but you sprang the trap. The sign of power can indicate direction as in: Pnet = Pfor - Pref or destructive interference as in: Pnet = P1 + P2 - 2*SQRT(P1*P2) -- 73, Cecil http://www.qsl.net/w5dxp I should have known I could depend on you, Cecil. 73 Tom Donaly, KA6RUH |
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