Activity for Olin Lathropâ€
| Type | On... | Excerpt | Status | Date |
|---|---|---|---|---|
| Edit | Post #291671 |
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— | 6 months ago |
| Comment | Post #291670 |
It's rather odd that your ground point is connected to a Professional Engineer. They aren't always that well grounded. From context I'm guessing you mean Physical Earth? That's not a common abbreviation I'm aware of. (more) |
— | 6 months ago |
| Edit | Post #291671 | Initial revision | — | 6 months ago |
| Answer | — |
A: ESD Table Earth Bonding Points - Why? I've never been involved with the design of an ESD table, so I can only imagine some reasons to put grounding connections at the front: For convenience. If you've got a table specifically for ESD reasons, you want to be wearing a wrist strap or ankle strap connected to ground. That has to be con... (more) |
— | 6 months ago |
| Comment | Post #291464 |
Don't create new questions to get around old ones being closed. Fix the existing question. There are still many things wrong even with your "fixed" version, like Hello/Thanks, lower case "i", formatting that makes no sense, the schematic in the top picture too small to read, etc.
Clearly you hav... (more) |
— | 6 months ago |
| Edit | Post #291464 | Question closed | — | 6 months ago |
| Comment | Post #291461 |
I closed this question because it was too sloppy. We do engineering here, which includes attention to detail. I gave up at the second "i". You talk about 5 FETs, but I only see 3. The schematic is very hard to read because it's so small. Certainly you can see this for yourself. You could easily ... (more) |
— | 6 months ago |
| Edit | Post #291461 | Question closed | — | 6 months ago |
| Edit | Post #291451 |
Post edited: |
— | 6 months ago |
| Edit | Post #291451 | Initial revision | — | 6 months ago |
| Answer | — |
A: Calculating base voltage of NPN transistor If this is a contrived homework problem where they are looking for an "exact" answer, then you have to solve a bunch of simultaneous equations. However, that would be neither useful nor anything you can rely on for a real world circuit. Real circuits have to work with transistors with widely vary... (more) |
— | 6 months ago |
| Comment | Post #291448 |
This question is too confusing in its current form. Post a schematic, and put any photographs directly in the question. How is 400 Kelvin relevant to this question? Links to datasheets might help, depending on what is really being asked. (more) |
— | 6 months ago |
| Edit | Post #291448 | Question closed | — | 6 months ago |
| Edit | Post #291419 | Initial revision | — | 7 months ago |
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A: Understanding inductive ringing are there more elements contributing to this effect that I have not placed in the circuit? Definitely, but it's hard to say how relevant they would be. The real world is messy. There is parasitic capacitance between every two conductors. Depending on what the dielectric is, some of those capa... (more) |
— | 7 months ago |
| Edit | Post #291387 |
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— | 7 months ago |
| Edit | Post #291387 | Initial revision | — | 7 months ago |
| Answer | — |
A: Standardized way of measuring AC line frequency There is no "standard". Do whatever works best for the situation at hand. In a microcontroller, it's usually easier to measure period than frequency, especially for "low" frequencies like the power line. If you are doing things in the micro related to the power line, then often it's the period y... (more) |
— | 7 months ago |
| Edit | Post #291386 | Initial revision | — | 7 months ago |
| Answer | — |
A: Power Line Filter. Location of Cy and common mode choke. For easy reference and to protect against possible edits to the question, here is the circuit you are asking about: In order to attenuate a signal, you need two impedances. Imagine you had a 0 Ω source at 5 V and wanted to make a 2 V signal from it. How would you reduce the voltage? ... (more) |
— | 7 months ago |
| Edit | Post #291350 | Initial revision | — | 7 months ago |
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A: Flash light frequency and rise time calculation The flashing-light frequency shall be 90+/-30 times per minute. I don't know what could be more clear. This spec says that the light must flash 90 times per minute, ±30 times per minute. In other words, the flashing rate must be from 60 to 120 flashes per minute. It should be obvious t... (more) |
— | 7 months ago |
| Edit | Post #291347 | Initial revision | — | 7 months ago |
| Answer | — |
A: How do we calculate signal rise time from frequency Your question is ambiguous. First, you need to define "rise time". That applies to a step, not a periodic signal. Let's say you have a 0 to 5 V digital signal. The rise time is how long it takes to go from the low state to the high state. However, that is still ambiguous. Let's say the sign... (more) |
— | 7 months ago |
| Edit | Post #291312 | Initial revision | — | 7 months ago |
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A: Control logic for mosfet in piezoelectric energy harvesting circuit I'll take it that you want this circuit to actually work, not just appear to work in some software simulation. In that case, it's about the circuit, not the simulator. A simulator is just one tool in designing or verifying a circuit. A brain and a calculator are usually much better tools. First... (more) |
— | 7 months ago |
| Edit | Post #291239 |
Post edited: |
— | 8 months ago |
| Edit | Post #291239 | Initial revision | — | 8 months ago |
| Answer | — |
A: What are these mystery components (one of wire coil, another labeled "100-10L A9")? The component with the coil of wire is an inductor. Judging from the small size, it is probably only a few µH. There are lots of uses for inductors, like for filters, switching power supplies, tuned oscillators, and others. I would not try to guess the use from this scant information. The... (more) |
— | 8 months ago |
| Comment | Post #291215 |
Make it readable, with properly defined axes. I see Andy has given you some suggestions. I'm not going to repeat basic presentation lessons you should have learned in grade school. (more) |
— | 8 months ago |
| Edit | Post #291215 | Initial revision | — | 8 months ago |
| Answer | — |
A: Determining the output swing, output common-mode range and input common-mode range in a differential amplifer First, common mode is something that only applies to a differential signal. When a signal is encoded in the difference between two voltages, the common mode voltage is the average of the two. The common mode range is the range of common mode voltage over which a small differential signal can stil... (more) |
— | 8 months ago |
| Edit | Post #291093 |
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— | 8 months ago |
| Edit | Post #291109 |
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— | 8 months ago |
| Edit | Post #291109 | Initial revision | — | 8 months ago |
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A: Regulated charge pump design That circuit is drawn rather obfuscated, but it does seem to make sense: Start by looking only at D1, D2, C1, and C2. Pretend D3, C3, and D6 don't exist. Although not drawn very well, this is a basic charge pump. For simplicity, let's pretend the diodes are ideal. The actual output voltage... (more) |
— | 8 months ago |
| Edit | Post #291093 | Initial revision | — | 8 months ago |
| Answer | — |
A: Step voltage 750kV lines It's really not clear what exactly happened in that video. We see someone slinging a hook over the power line, then we see a white picture. We don't know what the cable was made of and where the other end really was at the time the hook reached the power line. One possibility is that the cable w... (more) |
— | 8 months ago |
| Edit | Post #291082 | Initial revision | — | 8 months ago |
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A: MAX485 transceivers breaking, Pi filter generating spikes? At first glance, your design looks reasonable. I assume D1 and D2 are really supposed to be on opposite data lines, and them both being on the A line is a typo? One thing that sticks out to me is the value of the clamping diodes. Why so high? What's your expected common mode range? A large com... (more) |
— | 8 months ago |
| Edit | Post #291038 | Initial revision | — | 9 months ago |
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A: 1-wire interface overvoltage protection It's been a while since I did 1-wire, so I don't remember the current levels. R18 seems rather high for supporting the minimum required voltage at the maximum possible current. Let's say for sake of example that your 1-wire device is specified to work down to 2.0 V. You're already going to lose ... (more) |
— | 9 months ago |
| Edit | Post #291026 |
Post edited: |
— | 9 months ago |
| Edit | Post #291026 | Initial revision | — | 9 months ago |
| Answer | — |
A: MOSFET drain current ringing in saturation region Your controller is too fast compared to the plant (the thing being controlled), thereby causing instability. The most obvious culprit is the 50 kΩ resistor between the controller output and the FET gate. The resistor and the gate capacitance low pass filter the control signal, which effecti... (more) |
— | 9 months ago |
| Edit | Post #290863 | Question closed | — | 9 months ago |
| Comment | Post #290863 |
No. You didn't supply what was asked for. This question really should have been closed originally due to lack of information. I'll go fix that now. (more) |
— | 9 months ago |
| Edit | Post #290875 |
Post edited: |
— | 9 months ago |
| Comment | Post #290874 |
I think keeping the electrodes clean will be a problem. Gold should be inert enough, even in seawater. But the chlorine in the salt has a way of getting into everything eventually. Soldermask might survive long term in clean water, but I'd really want to do accelerated aging tests before expecting... (more) |
— | 9 months ago |
| Comment | Post #290874 |
Do you really only need to know whether the water is up to a certain level, or are you ultimately trying to sense the level. If the latter, there are some technologies you might not be aware of. A company I work for specializes in measuring levels in tanks, and things like the draft of ships. We h... (more) |
— | 9 months ago |