Timeline for $9\rm V$ Battery with $45^\circ$ phase
Current License: CC BY-SA 3.0
24 events
| when toggle format | what | by | license | comment | |
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| Apr 11, 2023 at 9:25 | answer | added | jpa | timeline score: 2 | |
| Apr 10, 2023 at 20:11 | answer | added | Aaron Hoover | timeline score: 2 | |
| Nov 21, 2016 at 8:41 | history | edited | Peter K.♦ |
edited tags
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| Jun 19, 2016 at 3:57 | history | tweeted | twitter.com/StackSignals/status/744378462937432064 | ||
| Jun 18, 2016 at 3:04 | review | Close votes | |||
| Jun 18, 2016 at 9:52 | |||||
| Jun 9, 2016 at 21:53 | answer | added | M529 | timeline score: 3 | |
| Jun 9, 2016 at 1:03 | comment | added | Dan Boschen | Thank you all for the good discussion and humoring my mental exercise with complex signals! | |
| Jun 8, 2016 at 17:04 | history | edited | Gilles | CC BY-SA 3.0 |
minor formatting
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| Jun 8, 2016 at 16:55 | comment | added | A_A | The dsp-puzzle tag is a great idea. | |
| Jun 8, 2016 at 16:35 | answer | added | hotpaw2 | timeline score: 3 | |
| Jun 8, 2016 at 15:33 | comment | added | Dan Boschen | Yes makes perfect sense; see Matt's answer. The reason for this question is people often assume "phase" with "delay" which of course would not apply to a DC signal. Yes phase can be defined against a reference, and in this case that still holds as the 9V battery with 45 degree phase is compared to a 9V battery that has 0 degree phase. The idea of a constant value (such as DC) with a phase has practical application in DSP, for example in the FFT implementation. | |
| Jun 8, 2016 at 15:26 | comment | added | Hilmar | This makes no sense. Phase can only be defined against so reference (i.e. phase between two things). DC cannot have phase. Can you describe an experiment or a setup at which the phase that you are ask for would be observable. Who would you know that there is a 45 degree phase or any other phase for that matter. | |
| Jun 8, 2016 at 15:24 | vote | accept | Dan Boschen | ||
| Jun 8, 2016 at 15:23 | answer | added | Matt L. | timeline score: 5 | |
| Jun 8, 2016 at 14:52 | comment | added | Dan Boschen | To clarify, a DC signal can have a phase, and the question is how do you implement it? This gives insight to someone that is new to certain aspects of DSP - the answer is very simple but if I say anymore than that I will give it away. | |
| Jun 8, 2016 at 14:43 | history | edited | Dan Boschen | CC BY-SA 3.0 |
changed phase shift to phase
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| Jun 8, 2016 at 14:42 | comment | added | Dan Boschen | I am defining phase shift as a change in phase of the signal. So perhaps the question is clearer if I drop the word "shift" as no change is involved and just ask how do you implement a 9V battery that has a 45 degree phase? | |
| Jun 8, 2016 at 14:36 | comment | added | Matt L. | Please define phase shift. Normally, an ideal phase shifter has a frequency response $$H(j\omega)=e^{j\theta\text{sign}(\omega)}$$ where $\theta$ is the phase shift. However, this doesn't make sense for a DC signal. | |
| Jun 8, 2016 at 14:34 | review | Close votes | |||
| Jun 8, 2016 at 17:04 | |||||
| Jun 8, 2016 at 14:27 | comment | added | Dan Boschen | It will be clearer once you see the answer, I just wanted to give people a chance to provide the answer, with DSP in mind. The point that a DC signal can have a phase shift is salient to understanding certain DSP processing so is a favorite question I like to ask my students in my class. | |
| Jun 8, 2016 at 14:23 | comment | added | Matt L. | There's nothing wrong with puzzles, but I wonder if this is about DSP, and - like MBaz - I wonder how you define a phase shift in that case. | |
| Jun 8, 2016 at 14:15 | comment | added | MBaz | Can you please clarify what do you mean by the phase of a signal with frequency 0 Hz? If $V_{DC}=|A|e^{j\phi}$, then the voltage is complex for any $\phi$ except 0 and $\pi$. | |
| Jun 8, 2016 at 13:58 | history | edited | Dan Boschen | CC BY-SA 3.0 |
Edited description
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| Jun 8, 2016 at 13:48 | history | asked | Dan Boschen | CC BY-SA 3.0 |