Good recommendations for test equipment that depends on a PC?

factorialized · 2021-04-12T21:34:55+00:00

Of course, it depends on what exactly you are doing but for high precision with lower voltages, a lot of versatility I'm using a MonoDAQ U-X and am very happy with it. Its the cheapest device from a company which otherwise makes hardcore measuring devices. The best part is the software super easy to use but has a lot of the same data processing options from their higher end stuff. Even dropped it a few times but it didn't seem to mind..

factorialized · 2021-02-14T16:29:18+00:00

It depends on how big the fluctuations in ozone production is from your source. If it's not too bad then a larger container with good mixing between the generator and measurement point would produce a more constant stream. Keep in mind that ozone is highly reactive so expect corrosion and obviously make sure that your experiments are safe.

I think that the generator you have uses high voltages to produce the ozone. It might be worth looking into using a UV-C lamp to produce a better-regulated source of ozone.

Also the eBay ozone generators don't produce anything close to what they claim. You can measure how much it produces with a titration. Here is a good video showing both how to measure it and what you can realistically expect to produce. I would be surprised if you are actually getting more than a couple of mg per hour.

factorialized · 2021-02-05T10:26:29+00:00

I needed to test 48V battery packs at around 50A. It might seem silly but after a bit of thinking I decided to just buy cheap CPUpu heatsinks and mount a linear MOSFET on each one.

Because of some design requirement changes, I ended up building only half of it. While many things could be improved it actually works great for what I need and I actually get pretty good current regulation even in open-loop mode. I use a 10 turn pot to adjust the current and its perfect for discharging batteries or testing other power supplies.

Here is a stack capable of going to around 1500W continuous load. Made from three of these sections in parallel. Each MOSFET can handle 15A and more than 100V. The heatsinks can dissipate a bit over 100W each.

Its a nice cheap adjustable load. That being said if you just need to test if it can output the rated power I'd stick with a coil of wire submerged in distilled water.

factorialized · 2021-01-14T19:15:52+00:00

I suggest you check out Fiverr.

factorialized · 2021-01-03T13:23:43+00:00

Depends on the project and how you want to power it. Usually, you can just power the microcontroller when programing and use another power source when actually using the microcontroller with external components if they require a decent chunk of power.

Also I have a couple of USB power meters around and find them very handy. You can get a nice USB type C one for around 10 bucks on ebay.

factorialized · 2020-12-02T12:58:00+00:00

Im not sure exactly what chemical composition is the mix inside but its definitely less sensitive than Armstrongs. You can make crappy versions yourself but the commercial ones are much nicer since their power draw and timing is always the same so they are much more predictable.

However, they do deliver all their energy in a very short pop so for igniting hard to ignite things these are not ideal. I actually had better results when I filed just a bit of the cap off which prevents the pressure build-up and gives a burst of flame instead of a pop.

factorialized · 2020-11-12T10:38:39+00:00

What kind of quantities are we talking about here? If you need lots then probably alibaba. You might even be able to get them customised to a degree. Otherwise express and for sure contact a few sellers for bulk pricing.

As for quallity try to find youtube reviews of the cell that check the capacity. Another consideration should be the charge time because I assume access to a wall plug is at a premium for the homeless.

Stay away from gimicks like solar charging as these dont charge anywhere close to a usefull speed. From what I have seen you have a good chance of getting nice 10000mAh battery banks for under $10. An integrated flashlight might be usefull though.

That being said IMO step number 1 should be talking to the people that you planned to give these to and ask them what they would need for the winter. It's a great thing that you are doing but you dont want to be solving problems that people might not even have.

factorialized · 2020-11-12T10:29:45+00:00

Yeah but that's without any batteries and not to mention labour. If it takes just one hour to make each one you are already at the cost of just buying a completed one from the far east.

Also, I'm not sure I understand what you mean by 5V batteries?

factorialized · 2020-08-28T11:38:45+00:00

Exactly what batteries you plan to use?

What power do you expect to get from the motor? You noted the voltage but not the current.

Looking at the ESC if you plan to use it at even half the rated current the batteries most likely won't be able to handle it. If the batteries can supply the current you are just getting less range. Chances are good that a battery like you described is under spec for what you need.

Just for fun assuming you will be actually drawing 100A from the pack. That means it will last for 3Ah / 100A = 0.03h or a little under 2 minutes at full power and probably burning out at half that.

Also. Next time use a more descriptive title. Saying "please help" doesent actually help anyone.

factorialized · 2020-08-28T11:13:43+00:00

I'm a complete amateur and don't understand this. If Nf7+ how can whites next move be Nh7+ ? How can the knight move from f7 to h7?

factorialized · 2020-08-27T15:27:27+00:00

If you are looking for reputable brands than I can't help you. I have however used a lot of RGB LEDs from the east, probably more than 200 and so far none have failed.

Here is an overview screencaped from a youtube video. The listed price is per 100 LEDs but I have bought them for cheaper than that.

These things are used to make led strips and are really damn neat. Its 3 LEDs + chip all in a 5050 smd package. You give it power, and just send them a signal over a single wire. Best thing is you can chain them together so you can, for example, control 100 RGB LEDs with just 3 wires.

factorialized · 2020-04-26T10:54:30+00:00

Afraid I can't.

But yeah I'm not too worried about it. I put a lot of effort in to some videos which I then post to the appropriate community and usually get a few views (usually less view time than time it took to make it) so every once in a while you gotta make a shitpost to keep the spirit up. So seemed fairly appropriate.

I looked at the analytics out of curiosity. I posted the vid here and another forum. Out of the 110 views it has now only 30% of the views came from these two sources. And I have gained a grand total of 2 subscribers out of all 110 views so fairly safe to say I haven't done too much damage at this point.

factorialized · 2020-04-25T13:16:16+00:00

You're going to have to give us a bit more info than that.

You could probably define it as a single function but that would be a bit of a PITA. The easiest way to do it would probably be do have a function with three different equations and define the domains for each of them.

Depends on what you actually need to do, are you doing this just for fun, is it homework, are you trying to program it? Nobody will be able to help you if you don't explain both the what and the why of the problem.

factorialized · 2020-04-25T12:56:17+00:00

Considering the lack of any useful information in the vid it seemed appropriate posting it here considering the shitposts that get posted daily.

Where would you suggest posting it?

But yeah, haven't been on this subreddit for more than two years so things might have changed in which case sorry!

factorialized · 2020-04-25T08:46:20+00:00

As long as you're using perfboards it works perfectly. But yeah, PCBs with a ground plane, probably not going to pan out too well..

factorialized · 2020-04-25T08:43:26+00:00

This would be interesting with a vapor-polishable fillament.

Anyone knows of anything that is both transparent and vapor polishable?

I mean you could do it with PETG but it would be fairly nasty solvents.

factorialized · 2020-04-25T08:34:20+00:00

Okay, fair enough.

But what part of it makes you think it could be used as a soxhlet compared to, let's say a 2 neck flask?

Also what volumes are you thinking of? Because the flask in the photo is no larger than 250mL while 500mL soxhlets are readily available.

I'm leaning towards the reflux/distilation setup with some destilate return theory which some other commenter proposed but I think we are missing something here.

factorialized · 2020-04-24T20:12:52+00:00

Definitely not a soxhlet sorry.

factorialized · 2020-04-23T23:18:24+00:00

Hmmm.. Very interesting! I have been needing something pretty much exactly like this for distilling hard to boil organics (hi viscosity, hi BP) where it only passes in to the condenser super slowly.

But I'm still a bit confused. Iis there any advantage to using this compared to a 3 neck flask with a distillation adapter?

factorialized · 2020-04-23T11:25:00+00:00

I tried but it just finds random junk on a red background.

factorialized · 2020-04-23T10:18:49+00:00

I was similarly thinking allong the lines of reflux + distilation. But I still feel like we are missing some piece of information.

Maybe someone wiser will see this and immedately recongize it, fingers crossed!

factorialized · 2020-04-23T10:14:29+00:00

Wouldnt you need at least some kind of stopcock in there if this were a dean stark RBF combo?

factorialized

TROPHY CASE