Activity for Olin Lathrop
| Type | On... | Excerpt | Status | Date |
|---|---|---|---|---|
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A: What is causing this massive discharge traveling down a power line? It is hard to know from a single static low-res picture, but my guess is that something caused a short across the high voltage lines. That could be a falling tree limb, a squirrel making an unfortunate hop, a bird with outstretched wings in the wrong place, some conductive debris blown across the wi... (more) |
— | almost 4 years ago |
| Comment | Post #280791 |
It's a number somebody picked from a whole set of tradeoffs. Note that 3.3 V is just about 2/3 of 5 V. (more) |
— | almost 4 years ago |
| Edit | Post #280714 |
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— | almost 4 years ago |
| Edit | Post #280714 | Initial revision | — | almost 4 years ago |
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A: Is it always necessary to use the ground terminal of the oscilloscope probe? Yes, you should connect the scope probe ground to the circuit ground near where you are probing. The unit under test (UUT) and the scope may have their grounds connected, but that is via a round-about path. This causes problems: The ground path can have significant impedance at high frequencie... (more) |
— | almost 4 years ago |
| Edit | Post #280676 |
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— | almost 4 years ago |
| Edit | Post #280676 |
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— | almost 4 years ago |
| Edit | Post #280676 |
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— | almost 4 years ago |
| Edit | Post #280676 | Initial revision | — | almost 4 years ago |
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A: Name of this current limiting device Your circuit It doesn't make sense that the yellow blob is a current sink: If it were a current sink, then there would be no point to the resistor in series with it. That only wastes power, reduces the compliance range, and doesn't change the current. You need to look at the whole circu... (more) |
— | almost 4 years ago |
| Comment | Post #280626 |
What you say works well when there is virtually no startup torque, like with a propeller. For loads that require some torque to move at all, you need to slowly rotate the magnetic field so that the 90° condition of maximum torque is guaranteed to occur. After that you assume the rotor stays locked ... (more) |
— | almost 4 years ago |
| Edit | Post #280609 |
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— | almost 4 years ago |
| Edit | Post #280609 |
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— | almost 4 years ago |
| Edit | Post #280614 | Initial revision | — | almost 4 years ago |
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A: Is a BJT 3-transistor Wilson mirror faster than a simple mirror? First Circuit Let's start by looking at the conventional current mirror circuit: The base of Q1 (Not sure which one that is? Use component designators next time!) is driven to whatever it takes to pass the current dumped onto the collector. Q2 is assumed to have identical properties, so it... (more) |
— | almost 4 years ago |
| Edit | Post #280609 | Initial revision | — | almost 4 years ago |
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A: BLDC motor - initial rotor position This is usually done by driving the motor very slowly open loop at startup. The idea is that the rotor will follow the magnetic field. Once you think the rotor is in sync with the drive, you speed up the drive and look for the back EMF. Since the magnitude of the back EMF is proportional to speed,... (more) |
— | almost 4 years ago |
| Comment | Post #280600 |
We don't know what you think a "half-Wilson" mirror is. If you want to compare two circuits, show the schematics of both of them. Also the current would be a step, not "ramping" up and down. Do you mean the *voltage* ramps up and down to nearly both rails? (more) |
— | almost 4 years ago |
| Edit | Post #280595 |
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— | almost 4 years ago |
| Edit | Post #280595 | Initial revision | — | almost 4 years ago |
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A: Why are two identical filters required for each signal, if the signals can be multiplexed into a single filter? There are a number of things that are unclear. You talk about the red and IR phases of the light sensor signal being demultiplexed into separate red and IR signals, but there is no evidence of this in what you show. If this is happening at all, the crucial information of what each filter is driven ... (more) |
— | almost 4 years ago |
| Edit | Post #280589 | Initial revision | — | almost 4 years ago |
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A: Why does AC frequency affect my microwave's RPM? The turntable is apparently run by a cheap synchronous motor. There is a type of motor that's easy to manufacture, that turns synchronously with the line frequency. You say the table used to rotate at 6 RPM with 60 Hz power, and now rotates at 5 RPM with 50 Hz power. That is exactly what you'd e... (more) |
— | almost 4 years ago |
| Comment | Post #280582 |
What documentation you need is already dependent on individual posts. If this site was getting 10s of questions per day, I wouldn't mind a new category. However, with the current volume it will only highlight the fact that there is low activity here. Look at what too many categories did to the Pho... (more) |
— | almost 4 years ago |
| Comment | Post #280582 |
I agree with what you said, but don't think a new category is necessary. These questions can already be asked in the main Q&A right now. The volume there is quite low now. If we ever get overrun, we can think about a new category then. (more) |
— | almost 4 years ago |
| Edit | Post #280566 | Initial revision | — | almost 4 years ago |
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A: How about a new section for code reviews? Personally I wouldn't want another category (what you seem to mean by "section"). I also don't think this should be a code review site. However, asking for validation and advice on small and specific pieces of code is already on topic, if that code is somehow related to hardware. For example, ... (more) |
— | almost 4 years ago |
| Edit | Post #280538 | Initial revision | — | almost 4 years ago |
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A: MOV vs. TVS diode You really have to compare datasheets. There are some general differences, but you shouldn't go by those in specific instances. MOVs usually have softer knees, are available at higher voltages, and are available for dissipating higher powers. Usually. One drawback of MOVs that they get "used up... (more) |
— | almost 4 years ago |
| Edit | Post #280532 | Initial revision | — | almost 4 years ago |
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A: Why is the Linear Time-Invariant System (LTI) dominant in Signal processing? Linear systems lend themselves to analysis since they follow certain rules. Because of this, much analysis has been done and theory developed, so there is now lots to keep undergrads busy with. Many simple passive systems are linear systems, or close enough so that they can be approximated as suc... (more) |
— | almost 4 years ago |
| Comment | Post #280450 |
@Lundin: The catching fire part was probably the visual effect of arcing. When the worker jumped out of the truck, he was probably still nearly touching it when he also touched the ground. This greatly reduced the insulating clearance, due to the body being essentially a conductor. The 700 kV jump... (more) |
— | almost 4 years ago |
| Comment | Post #280450 |
Why the downvotes? Somebody has to design these things, and the voltage they run at must be a consideration. Asking about the design tradeoffs is totally legitimate. (more) |
— | almost 4 years ago |
| Edit | Post #280458 | Initial revision | — | almost 4 years ago |
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A: recommendation for chip programming connection (pogo?) I have also had this problem for production runs of 100s to 1000 where you don't want to spend too much on a full fancy jig. Put plain round pads on the bottom of the board. 50 mils is usually a good diameter. Those work well with simple 90° pogo pins. Don't use holes. In my experience, a ... (more) |
— | almost 4 years ago |
| Comment | Post #280395 |
@Chup: That's not how data sheets work. (more) |
— | almost 4 years ago |
| Edit | Post #280395 |
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— | almost 4 years ago |
| Edit | Post #280398 | Initial revision | — | almost 4 years ago |
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A: What should be considered when picking a flyback diode? Catching a flyback pulse is actually a rather easy application for a diode. Many of the diode parameters don't matter much. The basics are: Reverse voltage. This is simply the maximum voltage the coil will be driven with, which is 24 V in your example. There is nothing magic about the flyback ... (more) |
— | almost 4 years ago |
| Edit | Post #280395 | Initial revision | — | almost 4 years ago |
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A: PCT2075 temperature sensor accuracy The text values in the specifications section are always the real specs. Unless otherwise stated (and that's quite rare), graphs are suggested values, typical ranges, variations due to a single variable, and the like. They are NOT specifications. The only accuracy you can count on is what it say... (more) |
— | almost 4 years ago |
| Edit | Post #280327 |
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— | almost 4 years ago |
| Comment | Post #280344 |
Done. See https://electrical.codidact.com/posts/280357. (more) |
— | almost 4 years ago |
| Edit | Post #280357 | Initial revision | — | almost 4 years ago |
| Question | — |
What should rep gain/loss be on Papers? The Codidact team has recently informed us that it is now possible to have different rep bumps on different post types. See this new answer by Monica to the old meta discussion that created the Papers category in the first place. Papers were always intended to be significantly more substantial wo... (more) |
— | almost 4 years ago |
| Comment | Post #280344 |
What's the rep change for votes now? Let's set the gain from upvotes to 3x that, and the decrease from downvotes to the same value (3x whatever upvotes are now, not 3x the current downvote decrement). (more) |
— | almost 4 years ago |
| Comment | Post #280344 |
Also, do what is most convenient with the existing rep. I don't care whether the rep bump from the existing papers stays what it is now, or gets re-calculated as it if happened on the new post type. Whatever works best for you. The rep from a few papers shouldn't be that much in the overall scheme... (more) |
— | almost 4 years ago |
| Comment | Post #280344 |
Thanks, that clears up some of my confusion. If it's easy to do, how about convert all posts in the Paper category to a new Paper post type, with ±20 rep per vote? ±30? I don't want this to be burdensome on you folks. It's a nice to have, but we are getting along well enough without it. Pa... (more) |
— | almost 4 years ago |
| Comment | Post #280327 |
@Andy: Maybe, but in the top picture you can clearly see that the loop has no effect on the other cable. It may be just a parallax thing in the second picture. I'll try to get back there and take more detailed pictures from better angles. (more) |
— | almost 4 years ago |
| Comment | Post #280344 |
If I understand this right (I got a little confused), you can't set the rep value of votes per category, but can per post type? Sounds strange, but I'm not a web developer. The proposal is then to create a "Paper" post type, and convert all existing posts in the Papers category to the new post type... (more) |
— | almost 4 years ago |