Activity for Olin Lathrop
| Type | On... | Excerpt | Status | Date |
|---|---|---|---|---|
| Comment | Post #288153 |
He probably used the same naming convention in his slides as in whatever book was assigned for the class. There are probably similar diagrams in the book, which should include better explanations for what the variables and axes mean.
I can't tell whether these are supposed to be diagrams in a sin... (more) |
— | 12 months ago |
| Comment | Post #288153 |
Where did you find these diagrams? There is probably some explanatory text around them. (more) |
— | 12 months ago |
| Comment | Post #288130 |
Hi, Jason. It would be nice to get more of the EE.SE core contributors to do what I did, but it's difficult to convince people, let alone reach out to them. It would be unethical to leave messages on EE.SE asking people to come here. You can say what you want on your personal profile, but that onl... (more) |
— | 12 months ago |
| Comment | Post #288030 |
More popups when clicking on the links. No thanks. I probably don't need the datasheet if you just said what these parts are. Are they opamps, A/Ds, D/As, etc?
Also, how does your circuit fit into the larger block diagram? What exactly is driving PREG_N? Is that one of the current sinks you ar... (more) |
— | about 1 year ago |
| Comment | Post #288027 |
I really don't want to follow links in the first place. Any information pertinent to the question must be directly in the question. Posting a link to a datasheet is valid, but then it must go *directly to the datasheet*. There is no excuse.
No, I'm not gonna even read what a popup says. And, I... (more) |
— | about 1 year ago |
| Comment | Post #288027 |
It's a bit unclear which blocks are sending and receiving and how they are connected. I tried to follow the link to your chip, but got a page with popups instead of the datasheet. (more) |
— | about 1 year ago |
| Comment | Post #287952 |
@#54288 Is the issue that you don't understand what it means for signals to have impedance in general? That's a valid question, but not something that should be buried in comments in a totally unrelated question. Ask about signal impedances in a separate question. (more) |
— | about 1 year ago |
| Comment | Post #287801 |
The speed Elsewhere has to do with how many people are watching and when the moderators are active. They have more people and more active moderators than here, more spread across time zones. You were originally offered to be a moderator, but you declined. I'd support you being a moderator if you'v... (more) |
— | over 1 year ago |
| Comment | Post #287773 |
@Lundin You are right, those resistors don't make sense. At total of 37.5 kΩ wouldn't let the relay turn on with 12 V as shown. I suspect something wasn't copied correctly. Maybe the C109 and 12 V are supposed to be on the left side of the resistors with high voltage on the right. Even then there... (more) |
— | over 1 year ago |
| Comment | Post #287746 |
Argh! Does that mean "microwave <i>oven</i> transformer"? If so, I just wasted time writing a lengthy answer that would have been rather different with this information. First, only use absolutely universal abbreviations in your question. Second, put the information directly in the question. Don... (more) |
— | over 1 year ago |
| Comment | Post #287746 |
What's a "MOT"? (more) |
— | over 1 year ago |
| Comment | Post #287728 |
You think you found what this circuit is called, but a "negative impedance converter" isn't a standard name I'm aware of. It's also the third circuit you posted in the same question, and quite different from the first that you initially asked about.
It's much more important to *understand* how a ... (more) |
— | over 1 year ago |
| Comment | Post #285186 |
Oops, you're right. The actual schematic is correct, and the device works as expected, but I apparently didn't pay attention to the dots when drawing up this less-cluttered version. In the real schematic, the secondary is flipped. The top part is connected to ground, with the bottom end feeding th... (more) |
— | over 1 year ago |
| Comment | Post #287689 |
@Freewill Only **you** can answer that question. We don't know your application and therefore how tolerant it is to noise on the sine wave. This is one of the questions we've been asking you all along.
If you can't quantify the parameters we asked for, you can at least explain how you intend to ... (more) |
— | over 1 year ago |
| Comment | Post #287689 |
*who want an inaccurate circuit* - The point is all circuits are inaccurate. You will always get an inaccurate circuit. The important question is then **how** inaccurate is tolerable. There is a wide spectrum of tradeoff between the various performance characteristics of a sine wave generator. Di... (more) |
— | over 1 year ago |
| Comment | Post #287689 |
*I finished by giving all information necessary to get helped:* - No you didn't. That's the problem.
*frequency range* - Yes, that's useful. That was clear in the question, so I didn't ask about it further.
*amplitude, current* - Those don't matter, because that would just be an issue for an... (more) |
— | over 1 year ago |
| Comment | Post #287689 |
@Freewill: I asked you several questions, but you only answered one of them, and then with an impossible value. We tried to help, but you wouldn't cooperate and do your part. If you want to continue, carefully read the questions I posed in the comment titled "Specs?", then specifically answer each ... (more) |
— | over 1 year ago |
| Comment | Post #287678 |
How accurate does this "sine wave" need to be? THD? Max error as fraction of full scale? Some other metric? How well must amplitude be controlled, like ±3dB over the full range for example? How do you set the frequency? How accurate does the result need to be to the setpoint? There are various p... (more) |
— | over 1 year ago |
| Comment | Post #287646 |
Saying to "never" use the auto-router is going too far. Auto-routers can be useful tools. But, as with any tool, you have to understand what it's good at and what not, and use it accordingly. You have to know your auto-router, what all the settings do, and make sure you set them appropriately for ... (more) |
— | over 1 year ago |
| Comment | Post #287535 |
This is a question and answer site, not a threaded discussion forum. If you have more information about the question, add it to the question. I have deleted your "answer" because it did not answer the question. (more) |
— | over 1 year ago |
| Comment | Post #287434 |
It's OK to answer Andy here, but you also need to fix the question so that everyone else can see too. Content isn't expected to be in comments. As it is, the question is inconsistent with itself. (more) |
— | over 1 year ago |
| Comment | Post #287434 |
There are several problems with this question that should be addressed:
1 - Trim your image! Those big black rectangles above and below your schematic are annoying at best. If you won't bother creating an easily readable presentation, why should we bother trying to help?
2 - Link to the datas... (more) |
— | over 1 year ago |
| Comment | Post #287400 |
*" you wish to use ..."*. I disagree this is the "normal" case. The CRT startup code shouldn't be making such assumptions. Lots of problems happen with hidden logic tries to automatically do things for you. You should get what you explicitly ask for. If you don't ask for something you need, that... (more) |
— | over 1 year ago |
| Comment | Post #287400 |
Nice writeup (+1), but I can't let this go: *"some dysfunctionally written CRTs do not set-up fundamental things like watchdog and clock settings"*. There are reasons you don't want to use a watchdog timer, or need more control over the clock settings than can be explained to the CRT. Good CRT star... (more) |
— | over 1 year ago |
| Comment | Post #287366 |
You have been told this before. Your diagrams need to be neat and readable. Your first diagram is so out of focus that we can't even read some of the component designators. The others are so small that they are difficult to read. You could easily expand them to fill the 640 pixel width available ... (more) |
— | over 1 year ago |
| Comment | Post #287359 |
I suppose that's OK as long as those users do the managing and regular maintenance. If you create that as a paper, I won't get in the way. (more) |
— | over 1 year ago |
| Comment | Post #287211 |
@LvW: Reading that over I realize I wrote that poorly. My F is the reciprocal of your F. I have updated the post to hopefully describe that better. (more) |
— | over 1 year ago |
| Comment | Post #287211 |
That's the same thing with F flipped. You can rearrange my equation to get Gain = G / (1+ G/F). I defined F as *"the fraction of the output fed back to the negative input"*. I suspect your reference defined F as the negative feedback gain. That's the reciprocal of what I used. Substitute this al... (more) |
— | over 1 year ago |
| Comment | Post #287196 |
Are Rin and Rl defined with the other end connected? For example, Rin must be right when a load is connected to the output, but can be different when the output is left open. The same question applies to the output impedance whether the input is connected or left open. I think you mean both input ... (more) |
— | over 1 year ago |
| Comment | Post #287027 |
A Siemen is just 1/Ohm. Ohms is a measure of *resistance*, not resistivity. The reciprocal of Ohms is neither. An Ohm times a length is a measure of resistivity. Conversely, 1/(Ohm-length) is a measure of conductivity. Siemens must be divided by a length to become conductivity. µS/furlong is a ... (more) |
— | over 1 year ago |
| Comment | Post #287027 |
µS is not a measure of conductivity. Fix your units. (more) |
— | over 1 year ago |
| Comment | Post #286988 |
Close reason: Raw homework dump. Read the rules. (more) |
— | over 1 year ago |
| Comment | Post #286862 |
I think you meant to say something else in the first bullet point. 180° phase shift already is an inversion. "180° inversion" doesn't make any sense either. (more) |
— | over 1 year ago |
| Comment | Post #286850 |
This device is basically a 32-channel ohmmeter. It needs to measure about 75 Ω to 40 kΩ to within a couple of ohms. Zener leakage is too unpredictable and temperature-dependent to calibrate out.
In the mean time, I used a circuit like what Andy suggested. The overall device is worki... (more) |
— | over 1 year ago |
| Comment | Post #286836 |
Closed. You were warned before. (more) |
— | over 1 year ago |
| Comment | Post #286793 |
I was referring to the opamp by itself. An ideal opamp in this case will have zero output impedance. I didn't mean that the zero output impedance is ideal for the rest of the circuit. In fact, I even pointed out how the inductor across the output is pointless in this circuit because the output of ... (more) |
— | almost 2 years ago |
| Comment | Post #286793 |
Oops. I meant to say high pass. Fixed. It should be doable without the resistor on the output of the oscillator. The right LC network can use the fixed input impedance of the inverting amplifier to control Q.
I'm not sure the OP is ready for these details yet. I haven't seen any evidence that ... (more) |
— | almost 2 years ago |
| Comment | Post #286792 |
You have been told this before. Use junction dots to show what intersecting schematic lines connect and which don't. For example, in the right diagram we can't tell whether only the bottom of L1 is connected to ground, or whether R1 and L2 also are. This is your last warning. (more) |
— | almost 2 years ago |
| Comment | Post #286766 |
In Eagle you can make generic symbols that can be customized with "attributes", which are sortof like environment variables that are set in the device. The device is what binds a symbol to one or more packages, and is a container for higher level information above the packages and symbols. Maybe Al... (more) |
— | almost 2 years ago |
| Comment | Post #286745 |
Still no schematic. (more) |
— | almost 2 years ago |
| Comment | Post #286745 |
You were warned several times about posting sloppy writing that you clearly didn't bother to proofread. I lost track what that runon sentence is about before even getting to the end. No, I'm not going to read it five times to figure out what it's asking, and neither should the volunteers here eithe... (more) |
— | almost 2 years ago |
| Comment | Post #286730 |
Don't tell me here. Put that in the question so everyone can see what is really going on. (more) |
— | almost 2 years ago |
| Comment | Post #286730 |
I'm not going to answer until you explain the larger problem this fits into. You have abused the volunteers here with very unusual requirements that you simply dreamed up, and that would not present themselves in a real world situation. Either explain the real-world problem you are facing, or menti... (more) |
— | almost 2 years ago |
| Comment | Post #286721 |
You fixed the image, but you haven't fixed the other problems I mentioned above. And, you added new problems. You have various combinations of inductance and capacitance being equated to dimensionless quantities. It doesn't take special electronics knowledge to get units right. Sloppiness is not ... (more) |
— | almost 2 years ago |
| Comment | Post #286721 |
I've told you before, the last time only three days ago, to post images that we can actually read. Not only did you not fix that one, but now you're here doing it again. This time I deleted it since there is no point in having unreadable images here. I also downvoted due to the gross sloppiness. ... (more) |
— | almost 2 years ago |
| Comment | Post #286705 |
Your original diagrams were already too small to read easily. Your new diagrams are worse. You really should be able to see that for yourself. The problem seems to be that you are trying to cram too much stuff into pictures horizontally. Keep in mind that any picture you post will be resized to a... (more) |
— | almost 2 years ago |
| Comment | Post #286700 |
@a concerned citizen: You should make this an answer. It shouldn't be buried down here in comments. When you do, I'll delete this comment chain. (more) |
— | almost 2 years ago |
| Comment | Post #286700 |
OK, "any" was too broad. "Any real-world" function would be better, since those can be decomposed to a set of sines. Since the system is linear, each sine component of the input can be treated independently. (more) |
— | almost 2 years ago |
| Comment | Post #286681 |
But your question starts out with <i>"I have to design a low-pass filter"</i>. Don't lie to us and jerk around the volunteers here like that. Two people have now wasted time trying to help you with this filter, only to find out the very unusual and difficult requirements were totally arbitrary. (more) |
— | almost 2 years ago |
| Comment | Post #286681 |
Then explain how you ended up with these specific requirements and what overall problem you are trying to solve. The question currently reads like a contrived problem, just like homework. (more) |
— | almost 2 years ago |