Activity for Olin Lathrop
| Type | On... | Excerpt | Status | Date |
|---|---|---|---|---|
| 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) |
— | about 1 year ago |
| Edit | Post #291461 | Question closed | — | about 1 year ago |
| Edit | Post #291451 |
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— | about 1 year ago |
| Edit | Post #291451 | Initial revision | — | about 1 year 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) |
— | about 1 year 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) |
— | about 1 year ago |
| Edit | Post #291448 | Question closed | — | about 1 year ago |
| Edit | Post #291419 | Initial revision | — | about 1 year ago |
| Answer | — |
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) |
— | about 1 year ago |
| Edit | Post #291387 |
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— | about 1 year ago |
| Edit | Post #291387 | Initial revision | — | about 1 year 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) |
— | about 1 year ago |
| Edit | Post #291386 | Initial revision | — | about 1 year 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) |
— | about 1 year ago |
| Edit | Post #291350 | Initial revision | — | about 1 year ago |
| Answer | — |
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) |
— | about 1 year ago |
| Edit | Post #291347 | Initial revision | — | about 1 year 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) |
— | about 1 year ago |
| Edit | Post #291312 | Initial revision | — | about 1 year ago |
| Answer | — |
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) |
— | about 1 year ago |
| Edit | Post #291239 |
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— | about 1 year ago |
| Edit | Post #291239 | Initial revision | — | about 1 year 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) |
— | about 1 year 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) |
— | about 1 year ago |
| Edit | Post #291215 | Initial revision | — | about 1 year 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) |
— | about 1 year ago |
| Edit | Post #291093 |
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— | about 1 year ago |
| Edit | Post #291109 |
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— | about 1 year ago |
| Edit | Post #291109 | Initial revision | — | about 1 year ago |
| Answer | — |
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) |
— | about 1 year ago |
| Edit | Post #291093 | Initial revision | — | about 1 year 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) |
— | about 1 year ago |
| Edit | Post #291082 | Initial revision | — | about 1 year ago |
| Answer | — |
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) |
— | about 1 year ago |
| Edit | Post #291038 | Initial revision | — | about 1 year ago |
| Answer | — |
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) |
— | about 1 year ago |
| Edit | Post #291026 |
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— | about 1 year ago |
| Edit | Post #291026 | Initial revision | — | about 1 year 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) |
— | about 1 year ago |
| Edit | Post #290863 | Question closed | — | over 1 year 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) |
— | over 1 year ago |
| Edit | Post #290875 |
Post edited: |
— | over 1 year 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) |
— | over 1 year 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) |
— | over 1 year ago |
| Edit | Post #290875 | Initial revision | — | over 1 year ago |
| Answer | — |
A: PCB as a wall of an underwater enclosure I guess it would work. I have used electrodes on a PCB to detect whether water level got high enough to turn on a sump pump. It worked, although it hasn't been installed very long. In that case the PCB extends upwards to where it is dry. That's where wires are soldered that go to the detection ... (more) |
— | over 1 year ago |
| Comment | Post #290863 |
What you are asking can't be answered without knowing the purpose of each connection to ground. We need to see both the layout (which you provided) and the schematic. (more) |
— | over 1 year ago |
| Edit | Post #290839 | Initial revision | — | over 1 year ago |
| Article | — |
Phone fix adventure case study I've had a Nexus 5X smart phone since 2016, so now in Feb 2024 it's almost 8 years old. I like the phone and have had no problems with it until three days ago. I had it in the car plugged in and connected as usual when I noticed it rebooting. I thought that was a bit odd, but figured maybe that wa... (more) |
— | over 1 year ago |
| Comment | Post #290785 |
@#8062: <i>"initially it could provide 10-15 minutes of runtime"</i>. Where did you see this? I looked all over for such a spec, but didn't find it. I checked in the user manual and on the web page the device was sold from. The web page just has a dash where the runtime would be (see above), and ... (more) |
— | over 1 year ago |