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Livethefire
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I had set up an inductive and capacitative ladder network to model a coaxial cable( or low pass filter)- 20 sections of L= 0.1 H and C=0.11 microF
That works out as a characteristic impedance of 953ohms.
The circuit starts at a signal generator, then 5ohms resistor before the low pass filter.
Using a signal generator set at 500Hz and +1V I sent a pulse down the line, terminated with:
A) 100ohms
B)953ohms
C)10000ohms
Measuring the output Voltage at equally spaced pins down the line allowed a plot of Voltage out over Voltage in.
B and C work out fine. B gave a straight line at one volt and C gave a line which the wave clearly destructively interfered with.. I can explain those with what i understand.
However what I cannot explain is when the line terminated with 100ohms. The plot I get with that seems really disproporatinate. It is a standing wave pattern that peaks at just over 6 volts. I can explain the shape and the reason for the shape (standing wave), but not WHY it peaks at 6 volts. I would have presumed 1+1= 2 asuming 100% reflection at the end (because I only put one volt in).
The blue one:
I tried the measurements again after doing a few differents things with the experiment and they seem to be stable at maxing out at 6.
I have looked into resonance but to my knowledge the resonant frequency of this circuit is around 1500Hz.
Any help or suggestions?
That works out as a characteristic impedance of 953ohms.
The circuit starts at a signal generator, then 5ohms resistor before the low pass filter.
Using a signal generator set at 500Hz and +1V I sent a pulse down the line, terminated with:
A) 100ohms
B)953ohms
C)10000ohms
Measuring the output Voltage at equally spaced pins down the line allowed a plot of Voltage out over Voltage in.
B and C work out fine. B gave a straight line at one volt and C gave a line which the wave clearly destructively interfered with.. I can explain those with what i understand.
However what I cannot explain is when the line terminated with 100ohms. The plot I get with that seems really disproporatinate. It is a standing wave pattern that peaks at just over 6 volts. I can explain the shape and the reason for the shape (standing wave), but not WHY it peaks at 6 volts. I would have presumed 1+1= 2 asuming 100% reflection at the end (because I only put one volt in).
The blue one:
I tried the measurements again after doing a few differents things with the experiment and they seem to be stable at maxing out at 6.
I have looked into resonance but to my knowledge the resonant frequency of this circuit is around 1500Hz.
Any help or suggestions?
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