Welcome to the Instructables Teachers Hub!

Welcome to the new home for all things Teacher related on Instructables. We hope you'll explore the new features and come back often to find and share projects, inspiration, and classroom resources. As you explore the new Teachers Hub, you'll see it's easy to find projects by subject or grade level and sort them to find all the best and freshest projects.Be sure to spend some time in the new Teacher Forum. It's a great place to connect with fellow teachers and make new friends! You could start by introducing yourself here or finding a topic that interests you and join the conversation there. :)We'll be working to continuously update and support your needs in this new area of the Instructables community, so thank you in advance for your valued feedback and suggestions.

Topic by WeTeachThemSTEM   |  last reply

Are you going to ISTE?

Anyone going to ISTE this year in Philadelphia? Is there anything you are excited to see or do there?Instructables will be at the Autodesk booth along with our friends from the Tinkercad and Fusion 360 teams. Come find us and say hello, and learn about some of our new teacher-friendly features. You can also decorate a tote bag and grab some cool swag!

Topic by randofo   |  last reply

Welcome to Instructables

On this page you can find links to some of our most frequently asked questions. What is this site? Instructables is a place that lets you explore, document, and share your creations. How do I post an Instructable? We offer a free and easy online class to coach you through posting your first Instructable or you can just wing it and start a new one today. How do I get help improving my Instructable?Ask the community for help in The Clinic. How does my Instructable get featured? The best way to get your projects featured is by following the Featuring Guidelines. Where can I learn more about contests? Our Contest FAQ has all of the information that you need to know about contests. What contests are launching soon? Check out our list of upcoming contests. Are you on social media? Yes! Follow us on Pinterest, Instagram and Twitter. How do I contact Instructables directly? The best way to contact us is through our Contact Page.

Topic by randofo   |  last reply

Water-damaged PCB repair

So water leaked in to the General Electronic Module (GEM) on my pickup and now it's acting all funny. A/C runs when the ignition is off, randomly switching to 4L, airbag light chattering on and off, etc. I want to try and repair it. My intuition is that it just acts up when there's stray conductivity between traces/elements, so if I give it a good clean and keep it dry it should work like new.However, I noticed upon pulling it apart that there's some corrosion taking place. Can anyone suggest a good way to repair these traces/SMD resistors? I have a soldering iron but heavily oxidized things don't take solder well in my experience. Or should I just put some lacquer on it and not worry about it?Thanks!

Topic by RelaxedSoup 

High School Teachers

Do you teach 9th-12th grade? If so, say hello and connect with other High School educators. Feel free to share where you are from, what grade level(s) and subjects you teach, and any exciting projects you did with your students this year or fun plans you have for your classes next year. :)

Topic by WeTeachThemSTEM   |  last reply

Middle School Teachers

Are you a Middle School teacher? If so, say hello and connect with other 6th-8th grade educators. Feel free to share where you are from, what grade level(s) and subjects you teach, and anything exciting you did with your students this year or plans you have for next year. :)

Topic by WeTeachThemSTEM   |  last reply

Elementary School (K-5) Teachers

Do you teach at the elementary level? If so, this is the place for you to introduce yourself and connect with other K-5 educators. Where are you from and what grade level(s) do you teach? Say hi and share something exciting you did with your students this year or project ideas you have for next year. :)

Topic by WeTeachThemSTEM 

Q: Others having difficulties about reading private messages in istructables profile page?

HiI just wonder, is it just me.. Or is there some known, wider issues on istructables page, that prevents reading private messages?I have tried couple days to read my messages, but when i click "Inbox", i end to the front page of the instructables, instead to my mail. :( ThanksTuomas

Topic by The other Finnish guy   |  last reply

Moon light timer

I would like to build a led light that switches on and off with the moon. On when the moon rises and off when the moon sets. Would also like no leds on at new moon and an additional led comes on until full moon is reached. The process then reverses an an led goes off until new moon with no leds on. I would also love the light output to be 4150k the colour of moon light and about 1 lumen at 1metre distance.

Topic by Ausie Steam 

555 monostable timer

I've no idea what I'm talking about here but can only explain what im looking for which is help. I'm basically looking for a relay or multifunction relay not really sure but here's the plan. When my smart plug is turned on (at certain programmed times through the smart plug app) to provide power to a 12v 6amp pump (I have 240v ac to 12v DC transformer pluged into smart plug I'm in uk) I would like for this pump to turn itself back off after 10 or 15 seconds. I cannot for the life of me find an analogue or digital timer that can do seconds. The smart plug can work down to minutes and not seconds. So basically smart plug on = pump run for 15 seconds cuts itself off and then the smart plug turns off once the minute is up and when plug is on again at next programmed interval it does same thing. Any help would be great as I've no idea what I can buy or try to make thanks When trying to research I hear about 555 monostable circuit but I don't know how to wire something up or what to buy to make this work.

Topic by croyf85   |  last reply

Sand carving

I’m new here and just wanted to share what I do. I have been glass sandcarving for over 20 years and used to teach it.

Topic by 1Sandman   |  last reply

Heavy duty UHF CB radio antennas and why cheap can be much better....

If you not a fan of normal road cars then you might get some 4WD and go off road every now and then.There are even those doing trips to remote locations that take a few weeks.An essential piece of equippment these days is a UHF radio.In a convoy you might get away with a handheld one if the cars are not too far apart and the terrain suitable.Most peole however opt for a permanent installation in the dash or roof console.After that decision comes the hardest and often costly part: What antenna to use....If you trust certain online reviews and manufacturer claims then one thing becomes quickly obvious.If you need a sturdy and powerful antenna then you have to pay top dollar.Some come with heavy spring bases claiming to protect the heavy fibreglass rod if you hit a bush or trees branch.There is always a compromise between weight and stability.And trust me, on the right corrugations you prefer not to look at your antenna....So how are these expensive antennas made?As I don't have any own pictures and don't want to steal them from the net: Please search for the terms used if you don't know them already.To answer this let me go to the other types of antennas you can get for your UHF radio.There is the famous rubber ducky - a stubby antenna best suited for short range on difficult terrian.Then we have the fibreglass whip antennas that have more or less coils integrated or even consist of one single coil with different spacings in sections.Good for normal road use, not so much off road as they won't tolerate too much vibration, they often snap off the base screw.Most people now just ignore the short whip antennas of 15 to 30cm length as they usually only come with a gain of around 4.5-6db.I will explain later why that might be a misconception.The last ones are those steel whips with one or two "loading" coils.These coils electrically shorten the antenna.They also provide a matching to the 50 Ohm required for most transmitters and antenna cables.Usually they are designed to be 5/8 Lambda antennas.A good antenna for just receiving, like when using a scanner is not critical in length.Transmitting however means you need a proper Standing Wave Reflection or SWR ratio.For this the antenna needs to be tuned.To be of any good use your antenna needs to match the transmitting frequency.This works best if the antenna length is at 1/2, 1/4 or 5/8 of the corresponging frequencies wavelength.Also called Lambda if you look for antennas.In the good old 27-MHz days we were used to quite long antennas in our backyard, for the car we then opted for 1/4 of this - usually around 2m in length.For UHF however 1/4 wavelength already means you are down to about 16cm...Going for 1/2 is a good thing here as it is still quite short at about 34cm.Real difference when it comes to these Lambda factors is the radion angle produced.You can imagine a 1/4 to look like a huge donut with no hole, about 25° for the radiation angle.At 1/2 this will be flattened out to around 20°.A 5/8 Lambda ntenna can get as low as 16°.Imagine it like a flashligh that has adjustable focus.The light source is of fixed output as your transmitter.The lens does the job of the antenna.If you make the beam more narrow then the light intensity of a certain areas at a certain distance will increase.Means for the radio you get a longer distance your signal can travel with enough energy.This however comes at a price!Imagine you are at the bottom of quite stepp mountain and your mate is up on the top about 2km above you.A high gain antenna with a narrow radion pattern might not even reach up there, while a short stubbie with just 3db still has a chance due to the more spherical radiation.Also explain why low gain and with that short antennas work best in hilly terrain...Back to the thick ones...As you can see you can basically hide any type of whip antenna into a fibreglass rod.But most of the are as said "ground independent", means unlike your normal whip they don't need the spring or foot to be of low resistance to your car's body.How does that work?Well, exactly like these ground independent whip antennas with a spring base or metal pole base work.You know the earliest antenna was a dipol - look it up on Wiki ;)For our CB radios that means you have a metal rod or spring that is about 1/4 or in some cases 1/4 of the wavelenght long.This is connected to the shielding of the coax cable and provides the required ground for the mounted antenna.The big difference is that only too often a dirt cheap dipol is hiding in your expensive fibreglass rod ;)The complete antenna might bring over 2kg on a scale, but the actual thing allowing you to receive and transmit is a few grams of coax cable...HOLD ON A MINUTE!! Some will say now...My whip is 70cm long and my expensive heavy duty one with 9db is 2m long - how does that work with your wavelength theory??Well, it is not my theory, just a fact ;)Imagine a 1/4 Lambda dipol, then it would be all up around 35cm long.And funny enough, that is about the length of a $180 heavy duty stubby if you just tak the rod itself.Go 1/2 of Lambda and you get an overall length of the dipol of around 65cm - add the metal rod making the crew that holds the fibreglass rod and you have the common 70-75cm heavy duty antenna...Anything above this length usually is either just a long rod with noting above the 75cm mark or simple has the 75cm long dipol made from the coax cable at the top with the antenna cable going down the otherwise empty rod.Ok, I got it, either 1/2 of the wavelength or 1/4, so about 35 or 16cm long.Ground independent we add either 1/4 for the spring base and rod or 1/2 for the longer ones.And how again does it work with the gain of an antenna?If you trust Wiki then it comes down to the radiation pattern.These heavy duty antennas usually come with around 6 or 9db, the short ones with 3-4.5db.These values might give you an indication about the theoretically possible distance you can transmit but nothing about the terrain it is suited for.Common rules of thumb created by those selling antennas and radios is that you a high gain antenna on flat terrain and a low gain antenna in a hilly area.Around 4.5-6db seems to be the golden ratio here as these anteannas are equally bad for both extremes in terms of terrain options.What you really would need to know is the actual radiation patterns in a three dimensional plane.A straight whip or dipol as a more or less donut shapead radiation pattern.However, location affects this!Mounted in the middle of the roof it is closest to perfect, while at the corner of your bumper bar you will distord the donut and also block parts out with the body of your car.This is why for this type of mounting elevated antennas are prefered.Makes no sense to have a 16cm long stubbie mounted so the top is still lower than your bonnet...Any antenna with a loading coil (or several) or top load will have a distinctively different pattern.We speak of so called "lobes".If you see it in 2D then for example a 1/2 lambda straight whip will look a bit like the infinity symbol.A 1/4 Lambda of the same style looks more like two ping pong bats joined without the handles.Those with loading coils or linear arrays made from coax cable however can produce multiple, prefered lobes.Usually they are in the 4-6db range and claim to be "universal" or as "allrounder".Here you get a quite narrow main lobe of 12-16° with one or more but much shorter lobes going upwards at about 10-30° depending on the configuration.At short range, like in hilly terrain both lobes overlap while you get a dead area at greater distances.You can sometimes notice that when you are on a low level talking to someone up high.There are cases when with a bit more difference in angle to each other (in terms of height and distance) the signal jumps up a few numbers.You just went from the dead zone into the lobe ;)With just a db value for the anteanna but no details about the actual design, heavy duty antennas can fool you badly.In mayn cases a 1/2 Lambda straight whip on the roof will outperform a costly, heavy duty antenna mounted to your bullbar.This is the reason why the expensive ones are the biggest cheat - they just elevate a quite small antenna above your roof line.And since it is heavy it needs a big spring and you hope it will not break if you hit something on a narrow track.All while the thin stainless stell whip with the cheap magnetic base just flexes under all obstacles with no damage at all.Plus, if you really get into the thick jungle you can just take the magnet off until you are through LOLWhy is a SWR and power meter still an important tool to invest into?Those remembering or still using 27-MHz radios only know too well why you need a proper SWR and power meter.With the lenght of the antenna at these low frequencies and affecting factors new the antenna proper tuning is a must.The bandwidth of the channels also means you have to tune the lowest and highest channel so the are basically even, anything else and the old guys would scream "UNACCEPTABLE!" ;)Especially it you want to get the last out of your system without going illegal.For some reason we accepted the claims that an SWR reading of around 1:2 is fine and acceptable.Most of the radios lower the power output to protect the transmitter if the SWR goes to far out.Allows for simple mass production of antennas with fixed cable lengths that are usually well overpriced.The most expensive bit is the cable itself here...I had no time to build an analog SWR and pwoer meter that works properly on 27 and 470MHz, so I ordered cheap SW30 from China.With that I first checked my little collection of antennas then those of some of my friends.This includes everything from short rubber duckies over loaded and straight whips to heavy duty models.One thing that was obvious right away: most are far away from an SWR readin anyone with a 27MHz groundplane antenna on a long mast would accept.And only one heavy duty antenna had a SWR readin of below 1:1.6 for channel 1 AND channel 40!That one was relatively cheap noname brand.With that sorted I decided to tune at least my steel whip antennas.To my utter disappointment they were all just a tiny bit too short - a thing that would have caused a proper 27MHz antenna manufacturer to to keep a large stockpile of his antennas...I had one though that was longer than needed.And before you ask: Yes, I tested them on both my elevated bullbar mount AND a direct mount on the roof rack.Did not change much for the bad ones so I ignored the mounting position for the tuning.I checked the power once for both channels on my prefered antenna and got 4.4W.Mind you that one has a SWR reading of 1:2.2 and will no longer be used as I can't be bothered to make it longer.For some reason I thought I check the SWR and power everytime I cut a bit off the antenna instead of just watching the SWR reading.At original length I had a SWR of 1:1.9 on ch40 and 1:1.75 on ch1 with 4.6W.I kept trimming down by about 2mm increments until I got an even readin of 1:1.07 on both channels.And with every trim the power went up a little bit.I have a friend that is or better, was just at the brink of being unable to reach from my driveway when he is parked in front of his house.A radio check after the tuning revealed that instead of coming with a lot of static noise and sometimes cut out I got a solid reading of 2 on his end with a much more acceptable level of noise.However, I still struggles as badly to hear him...Funny thing is that test was with just a plain and straight whip of 1/2 Lambda, in my case the tuning resulted in a length of 38cm from the base of antenna screw to the tip.My fancy 9db high gain antenna that is just over 70cm long did not even reach him while I could hear him slightly better than on my tuned one.Changing the mounting to the roof rack gave me a clear reception and a signal strength of 4 at my friends end with no noise.Elevation and nothing around the antenna does matter...After all this, would I still bother to buy a ready to go antenna for 470MHz?Only if I had to.Getting some RG58 cable or re-using it from on old antenna is cheap enough.A standard screw mount with a grub screw to hold a steel whip sets you back less than 10 bucks, from China even cheaper.And most will find a soldered on connector on the other end of an old antenna to be salvaged if required.If you don't have any sring steel wire of about 40cm length then think out of the box ;)The packing of pillows and such often come with a sring steel wire to make the plasitc floil keep its shape, some old suitaces have thicker wire doing the same.And if you ask nicely you might get a bristle or two for free from a street sweeping machine at your councils depot ;)After all we only need a maximum of 40cm to have enough left to trim and tune down.What is left to do?Of course some distance tests to check how well such a simple antenna really really works in comparison to commercial models.I only have one 9db antenna and will check it first to see if on flat terrain there is much difference in distance for transmitting.Unless this difference is well above one kilometer I will not bother with a high gain antenna like this anymore and instead opt for a longer mast and 1/2 Lambda.Another thing on the to do list to try a ground plane antenna with topload to squeeze the radion lobe down to under 15°.The resulting antenna would be quite short here and using an elevated mast is a must have to get over roof level with at leat a few wavelengths of distance to the roof.I guesstimate that an optimised antenna of this style should result in a distance increase of about 10-15km of flat terrain while being utterly useless in a hilly areas.Plus, such a design is not really suited for a vehicle going fast on a freeway, so it will go on my house instead.

Topic by Downunder35m 

Not able to access drafts

Whenever I click on the drafts button to edit my ice cream Instructable,, It sends me to the Instructables home page. Is this just a glitch or am I doing something wrong?Thank you!Wozzell11

Topic by Wozzell11 

Tesla coil antenna?

With the cold and bad weather out there I started again to tinker with my old UHF radio.Trying to build a nice antenna to put on the roof of the hous and such things...While looking up on the various antenna designs I could not help it and followed a few links with antenna designs and specs for all sorts of frequencies.There are things like horizontal or vertical transmission waves or even circular ones.But also some of the basics can be quite different, like whip antennas, dipoles or coiled ones.The later we often see in these keyfob transmitters and receivers for door bells and similar low range, low cost options.Some really old ham radio links got me to the topic or electrically shortening and lenghtening antennas.Things like coils in a whip or added capacitors to match the antenna to frequency and transmitter.A tesla coil usually produces a lot of RF interference, not just on the main frequency it operates on.And from research and physics we learned that for really great distances you need really low frequencies.Like for example the very low bands used for submarine communication around the globe.Here antennas on land can be several km long...The inventor had a few ideas in terms of wireless electricity and communication but I wonder if there is more to it...Despite the broadband EMF a tesla coil produces it is also a really narrow beam antenna.Basically the radiation cone is orientated straight up instead of the usual horizontal patterns we use for communication.The topload again provides a spherical radiation pattern.I am wondering about how a tesla coil would operate as a directional antenna if the topload is replaced with a whip style antenna of a lenght that matches the wavelength...The hip would again provide a more or less spherical beam but the coil underneath would "puch" a directional from underneath.In the classic design the topload is meant to prevent arcing while providing a capacitor so the whole thing is resonant.At lower power arcing is no problem anyways, but what effect in terms of capacitance would a whip style antenna have?Classic pherical or donut style toploads provide little to no gain in terms of antenna properties.If you would use a sphere as an antenna for your CB radio then it would be perfect for very short distance but utterly useless for open range communication.We all know the fun of placing a flourescent light near a tesla coil to show "wireless electricity".Sadly this is more an effect caused by the high frequencies be able to produce the glow in the gas filling.Trying to make an incandescent lighbulb glow is far trickier.Several experiments show that two properly tuned tesla coils can work as transmitter and receiver.But to my knowledge no one ever tried this type of experiment with an antenna on the tesla coil...

Topic by Downunder35m 

Need help simplifying project (Raspberry Pi + Pi Musicbox + NFC Reader)

Hello.I have a desire to build this project - https://github.com/brendandawes/PlasticPlayer.But I'm a total layman in hardware.TL;DR: Media player based on Raspberry Pi and Pi Musicbox (mopidy), with the Espruino + NFC reader used as a track selector (NFC cards store the track id which is then cross-referenced through a database).Upon close examination I think the additional Espruino is redundant (especially in the way author made it, so it talks to Raspberry via wi-fi), and I would like to connect it directly to Raspberry Pi.I've ordered the Raspberry Pi recently, and it hasn't arrived yet, so I can't really tinker with it. So asking the question ahead.Taking into account that Pi Musicbox will used as the base system, what exactly do I need to do, so that it can control NFC reader?How can I create a program to control Raspberry Pi GPIO? Is it possible to make it compatible with common libraries that are available for NFC reader?Thank you.

Topic by beshur 

Is it possible to connect an led in parallel with a lock mechanism?

I am working on a project. I have a keypad panel that unlocks a door and I want to add in the circuit an led indicator(when the lock is released I want the led to turn on. When connecting the lock with the led in parallel the keypad does not work properly. The lock uses 1amp and the led needs less than 350ma. Would a resistor on the led solve the problem? If yes, what resistor should I use? (it's obvious I don't know much about electronics but I wish to learn...). Any ideas or ideas or advice is most welcome! Thanks community!

Topic by DimiLa   |  last reply

Hp p 2015 bldc motor pin identification

Please tell me pin out details of RK2 1567 laser printer motor . it's supply voltage.

Topic by devsupercom87   |  last reply

Finding a very special screw

This cross stood on our wedding cake 50 years ago. The cross has three parts: the cross itself, the domed base, and the anchor rod that goes down into the cake. A threaded end on the anchor rod passes through the domed base and into the bottom of the cross. My wife gave me the task of finding a screw to attach the base without the anchor rod so she can stand it on a tabletop.I suspected that the threads are metric because the cross and its parts were made in Germany. Screws at hardware and fastener stores in our good-sized municipality are as small as 4mm, but this is smaller, probably a 3mm screw. I could order half of a dozen on eBay, but they would arrive only days before our guests come for our celebration. If anything did not work, I would be stuck. From photos by eBay vendors I guessed the screw I need is size M3 x 0.5. I poked around on the Internet and learned that M3 x 0.5 screws are frequently used in laptop computers. My laptop has some of those for holding the case together. I borrowed one of them for a couple of weeks until after our guests have gone home. My laptop will not miss the screw for a short time. Keep this in mind if you ever need a screw not available locally. Something you already have may be a suitable short term donor.

Topic by Phil B   |  last reply

Home page

I am at a complete loss as to why the most recent projects are not on the home page. Some of the projects shown date back to 2014!!! There seems to be no logic as to what is being shown.I hate to say that the previous version of the site was better when some of the improvements are great and it looks a lot better; HOWEVER, being able to see all the most recent project (whether featured or not) from the home page was great and it gave us makers something to aim at. It now seems that posts will be basically hidden unless someone is following you or the group that you post you.PLEASE bring back a simple way to see all submissions to instructables so that all authors get their moment of glory! Hiding recent and new featured posts within individual feeds does not provide that wide and varied community feel that the website use to have as soon as you opened it. Aaarrgghhh!!! now I can't figure out how to post this without putting it into some unrelated category!!!!

Topic by RCEM   |  last reply

Website-BUG: Mailings of comments has invalid links

If i get a mailing about a new comment, NONE of the links work i get sent:Comment tracker (https://www.instructables.com/member/[username]/comments) bounces back to instructables.comThe reply-function @ https://www.instructables.com/member/[username]/c... bounces back to instructables.com/[key] but the [key] has no functionality there, so it basically bounces back to instructables.com as well.and yes: I AM logged on and the other website bug i wrote about is not to blame:i renewed the cookie on this PC just to be sure.

Topic by Orngrimm   |  last reply

Website-BUG: Login-cookies mishandling

Looks like the report over in circuits got lost and didnt catch the eye of the devs.https://www.instructables.com/circuits/community/W...lets try cooking homebrew...

Topic by Orngrimm   |  last reply

Laser Cutting in the Classroom

After creating a makerspace at my elementary school, I was always on the lookout for fresh projects and new tools and a laser cutter was that one big item at the top of my wishlist that I just never got... but, I know some teachers and librarians who are brand new to the world of laser cutting and would love pointers from other teachers who have already worked through some of the challenges of starting something new. :) So, if you have a laser cutter in your classroom or school makerspace, please share any tips or suggestions you might have for any teachers who are just starting out with one at their school. Also, feel free to share any cool projects you and your students have done or programs you use.

Topic by WeTeachThemSTEM   |  last reply

Makey Makey Community Hub

We are stoked to be part of this new teacher community! Thank you, Instructables! We are going to have our own community hub soon, and are hoping you'll want to be a part of it! Do you have a Makey Makey guide that you've created for your classroom? We'd love to see it and share it on our hub! Share a link in this topic to show us what you've made.

Topic by MakeyMakey   |  last reply

A helmet of Assassin's creed's alexios

I am a fan of Assassins and want to make a Assassin's creed character alexios helmetHere it is

Topic by nischayajoon 

RGB Led doesn't mix colors

Hey all I am working with common anode RGB LED. I hooked each leg (red, green, blue) to pins 2-4 of my Arduino UNO. I then hooked the anode to 5v via a 22 ohm resistor. The code I wrote was very simple; turn pins 2 through 4 low, delay 500, turn pins 2-4 high. The problem I found was that instead of the color turning white it stayed red. I tried mixing red with green and red with blue, each time same thing it stayed red. Does this sound right?

Topic by Mpc1055   |  last reply

Favorite 3D design programs to use in the classroom?

I have been using Tinkercad from the beginning and really like how easy it is to use.I'm curious what 3D design programs you find easiest to use and teach? Do you feel there some are better for different age ranges than others?

Topic by Penolopy Bulnick   |  last reply

Project-Based Learning (PBL) Resources

I'm always inspired by the awesome, in-depth projects teachers are doing with students in different grade levels. From animal research projects in second grade to designing 3D models of Jamestown in Tinkercad with fifth graders or CubeSat projects in High School. There's so much we can learn about PBL from each other! :)What are your "Go To" projects that you do with your students? Any tips for managing class projects and grading (rubrics or scales, etc.)? What about finding materials/resources for projects? My best resource for cardboard was the school cafeteria. :D

Topic by WeTeachThemSTEM 

How do i disable an auto clip limiter?

I have an eb7500pro rack mountable amp running 1800 watts rms in bridge mode and i cant get the amp to turn up to clipping i would like to. i know your not suppose to clip the amps i know all the possible dangers when entering clipping zone. when i turn up the amp to about half 1over4 of the way up and the volume decreases. and when j turn it down the volume kicks back in. when that clip light emits it turns down the volume I know because i play a constant hz tone and slowly turn it up and it turns itself down how do i stop that?

Topic by samhenderson156   |  last reply

HELP: Measuring power density from cellphone tower.

I am working on a project to measure the power density from cell tower. Most projects I saw involve expensive antenna and also a spectrum analyser which is too costly. I came across showing ppl fabricating a target single band microstrip passing through a RF Detector circuit. I think chip like AD8318 could handle it?? But how am I gonna filter if were to use an antenna with range of 200MHz to 2GHz eg. (https://www.sparkfun.com/products/8347) to measure a specific GSM band like 900/1800 MHz from the cell tower? I need help on the filtering and RF detector circuit part!!The closest resemblance to my proposed system: https://www.favoriot.com/category/how-to/

Topic by StudD   |  last reply

Archery Load Cell Circuit

I'm looking into a system that will enable me to determine the distribution of load on an archer's draw hand grip, probably as a percentage of the whole load. I have some basic ideas drafted, but before I start re-inventing the wheel, has anyone anything similar set up that I could look at or consider developing.The sensors/load cells must be able to fit between the two layers of a standard archery tab. There must be three sensors, for the three fingers of a normal "hook" grip, and I think either an Arduino or Pi based processor.

Topic by Warleyman   |  last reply

School Project - Arduino Personal Locator Beacon

Hi All, I'm currently in Year 12, undertaking my major design project.I have chosen to design and produce an emergency survival kit that comes with an in-built personal locator beacon. The personal locator beacon must have the capability of transmitting geolocation data to emergency services for atleast 72 hours. It must be able to work in remote areas.I have purchased a range of parts in order to help create this project, of which, I will list below.- Arduino Uno r3 Development Board- Arduino compatible Long Range LoRa Shield- Arduino Compatible GPS Receiver Module- 2600mAg Metallic Power Bank- 5/5.8GHz 5dBi Wireless Networking AntennaI have been experimenting with Ardunio & Components for a while and now understand the basics. I have managed to get the GPS module to work and receive geolocation data. However, I have only been able to do this when the Arduino is plugged in and powered by a computer. For my project, I need to be able to send geolocation data to a specific source, whilst on the go, in remote areas.I plan to power my components by using a portable power pack (similar to a portable phone charger), however, I am unsure of how to program the gps module to send geolocation data to the long range shield, which will then send the geolcationd data to emergency services (it can be a proof of concept but it needs to be communicated to something such as a cell phone or a radio frequency).I would really appreciate any advice or information that can help me develop this project or point me in the right direction. Kind Regards,Adam

Topic by awsomeclone2218   |  last reply

Website-BUG: Login-Cookie-Handling over multiple PCs with feed

I had this problem in the past sporadically but never saw a pattern till recently:I come to instructables.com, i am already logged in and click on "feed" at the top.After a while an error pops up telling me a Rerouting-error happened. (Umleitungsfehler in German).I noticed, this always happens after the following action-pattern:- I visit instructables.com and log in on computer A and i DONT log out there but only close the browse.- I visit instructables.com on computer B. I am seemingly already signed in from the last visit here on Computer B at instructables.com. - If i now click feed (On Computer B), the error happens.- If i logout and log back in on Computer B, the error is gone on this computer B, even over Firefox-restartsAs far as i undestand, as soon as i log in on computer A, a new login-cookie is created on Computer A and the cookie on Computer B will no longer be valid next time.Now, if i come to instructables with computer B, the cookie somehow still is interpreted valid and logs me in (I appear to be logged in with my avatar visible at the top right). However, if i want to go to my feed, it seems Instructables checks again the cookie and figures out that i have a no longer valid login-cookie on this Computer B due to my login on Computer A and refuses to redirect me to my feed. This gets sorted with Re-Log on Computer B, creating a NEW login-cookie on Computer B and all is well again on Computer B. Now i can play the same game on Computer A with re-log. :)I hope, this error-report helps you guys in pinpointing and fixing an issue with a Login-bug as it seemsAnd Why to hell do i have to define in which channel this belongs and you dont have a channel "website of Instructables"?!? I hope this is not lost in "Circuits" - "Software" which was the closest i could find to a website-problem... Geez...

Topic by Orngrimm   |  last reply

Q: can i power a (9v-battery) multitester with 8 or 10v?

Hi, i´m living in a mountain-cabin with a small solar-kit (12v battery, 6 x 2v cells).i want to buy some multi-tester (which normally uses a 9v battery).i hate to buy batteries (and not just becauce i am a cheap fukc - might actually cost about a bit less than the tester itself, go figure, beauty/beast of capitalism)since i got anything from 2-4-6-8-10-12v here (for free - thank you sun): can i run the tester with 1 volt more or less? (or does all hell break loose .. which i´m actually kinda fond of)bowing

Topic by la xerra   |  last reply

Tips and tricks for UV curing glue, resin and coatings

Only a few years ago your only option to repair certain plastics, glass or even a broken crystal was epoxy based resin or the good old superglue.You might have already tried one of the 5-seconds-repair pens or tried your own UV curing nail polish art at home.For the later you might be lucky as the resins used here are optimised for the purpose and lights you get with them.Sadly even the best nail polish is no substitude for a glue as the material properties need to be different.One of the most common complaints when it comes to using some UV glue, like Kafuter or similar is that it never comes with instructions.Sould be straight forward but it is not free of problems.For example almost all commercail UV curing glues that you can buy require quite stirct procedures and for the light the right wavelenth(s).Resins and coatings can be even more painful here as they might also require you to stick to the correct temperature.Let's start with one thing you might have encountered already...The glue is definately cured and rock hard but the surface tacky and smeary.Quite annoying if you want to fix a piece of jewellery and can't prevent it from collecting dirt and dust...The next thing you might have encountered is that despite having transparent materials it seems to be impossible to cure the clue.Both problems come down to wavelenght and exposure.UV curing glue is prevented from curing in the presence of oxygen - a factor utilised for example in resin based 3D printers.Uncovered glue is exposed to the oxygen in the air and won't cure easy.The glue or resin below this layer however with fully cure with ease in the absence of oxygen.For the second problem consider that not all materials that you can see through will let UVC light pass through ;)Bonding strenght is another complaint I hear a lot...Be aware that certain things just are no good for UV curing glues or resins.Take the molds you get for that purpose: on the material the glue won't bond!Teflon is another prime candidate here.But in a lot of cases it comes down to surface preparation.Don't be afriad to sand the surface!Not only will the surface area increase but the scratch marks will be invisible once filled anyways.Use sandpaper on your fingernails, then go over with clear nail polish -mirror finish ;)With curing often a problem consider to fully cover the glue.A bit of clear sticky tape, food wrapping foil....If that is not an option then eliminate the oxygen.You can use a container filled with inert (for the glue) gas like CO2 or just place a burning candle in it until it goes out....Either way the amount of oxygen should then be low enough to cure the surface of your glue.Not always is any of the above an option.Then you can still try more power and a lover wavelength.Mercury based lamps for example provide a very broad and powerful light that in most cases will cure within seconds.For a proper surface cure you need a wavelength of 265nm or lower.LED's offering this exist but at prices well out of range for the hobby user.A mercury lamp under high pressure is nothing for short term use and the limited lifespan does not always justify the costs of buying them.Like with most things in life certain inventions can have a dual purpose.Quality germicidal lamp systems for examples often state to go as low or even lower than 265nm.And they come at a fraction of the cost you have with a broadband mercury lamp.Even cheaper is the fre weather forecast.If the sun is siad to be strong enough so you need protection than even the worst glue will fully cure in seconds outside in the sun - tackfree!Don't be fooled and protect yourself!!These tiny LED lamps for your glue stick, the curing thingies for your nailpolish and everything else using UV light comes with warnings.For very good reasons!It might be hidden in the fineprint but you can not really see UV light.The blueish-purple glow you see is on the high end of what comes out and by that in the visible range of your eye.Just because a LED only gives a faint glow you see does not mean the UV light wouldn blind you if you could see it!Even worse for fluoroscent lamps or open cruning systems like those for your nailpolish.Reflected UV light is still UV light and you can still NOT see it!Stories of people getting sunburnt from germicidal lamps in a butcher shop or other people going blind from checking money as their living have a true base...In most cases lamps used well past their lifespan or simply the wrong type of lamp but still: the damage came from UVC light...If you just love creating your own artwork or jewellery with UV curing resins and glues than protect yourself.Proper sunglasses with a stated UV protection for example or just black nitrile gloves for your hands...

Topic by Downunder35m 

Change yarn colors ?

How do I change yarn colors in crochet With pictures?

Topic by Godloveus1962   |  last reply

How much water is in my cistern?

I built a 33 gallon cistern my garage to collect condensate from my HVAC system. (I didn't have room outside my condo for a rain barrel). It has a spigot and a short hose, it lives above my utility sink, which is where the overflow goes when the cistern is full. I'm hoping some clever makers can give me some ideas on how I can build something that will tell me how much water is in the cistern. I have Samsung SmartThings so I've considered putting a water sensor just below the overflow hole, so I will know when it's at 100%, but I would prefer to have a percentage reading and an alarm when it gets to 90% or so. I considered an arduino with an ultrasonic sensor but that a bit involved... Not opposed to it but please be prepared to hold my hand thru the process of you propose it! ☺. Non-SmartThings solutions also welcome.Thank you - looking forward to your genius ideas!!Mark

Topic by MarkB673   |  last reply

Rewinding a DC motor for different voltages

I modified small DC motors, like used in toys and such but now I have one that requires to do it properly.Motor in question runs on 24V and uses about 3.5A under full load.Drives a high pressure water pump on either side of the shaft.The rotor is basically empty with just a few turns of wire and lots of empty space.I assume the same model is used for multiple power configurations by the manufacturer.For the toys my basic approach was to just calculated the number of turns or to count them when removing.From there I get the voltage per turn and can rewind accordingly.So in theory and by blissfully ignoring all higher things involved I could do this motor the same way.Right now I see 10 windings per coil, so with thicker wire I would use 5 to run it on 12V at roughly the same speed.Only problem is that thing then would use around 7.5 to 8A when running under full load and get quite hot.I need the speed to keep the flowrate at the same 7.5L per minute but I also need the power to be able to still get the 120PSI from just 12V.Isn't there any winding trickery that would allow me to reduce the required current a bit without sacrificing on speed or torque?

Topic by Downunder35m   |  last reply

D.i.y. (plastic) nuts (for any kind of thread)

For emergencies or simple application: how to make your own nuts out of (p.e.t.)-plastic bottles:take a bottle (#1 plastic, preferably smooth, w/o imprinted patterns or design etc) > cut off bottom and neck > start cutting (scissors) > the resulting ´tube´ into a consistent (width, depending on desired usage), slightly diagonally, thus sort of ´peeling´ it > wrap the strip around the screw/threaded-part/etc you need the nut for twice (for a start) > ´melt´ the edges of the wrapped part = joining them (i use a little solder-iron) > this way the wrapped beginning of the strip wont come loose > ´brush´ with the solder-iron (or whatever other source of heat) over the wrapped part (w/o) burning holes in it > this causes the plastic to shrink and press down into the thread and adopt its shape > once set keep doing more wraps of the rest of the strip until you reach a desired diameter > now, again, join the edges of the wrap with heat, and afterwards brush again over the outside of the created ´nut´, so that the plastic shrinks down & compacts > after having cooled off: unscrew the ´nut´ with pliers > ready for useps this is just a simple sketch. got no camera to take photos. sorry. so, please, ask whatever if you got any question. and any kind of feedback is more than welcome. bowing.

Topic by la xerra   |  last reply

What kind of repetitive elements can you use on a surface with a gluing material inbetween to decorate it and look luxurious?

What kind of materials/repetitive elements/items can you use on a surface with a gluing material inbetween to decorate it and look luxurious?Check my pinterest folder, I want to make a parametric/curved wall ( https://i.pinimg.com/564x/34/e4/04/34e4045e39debc... ) and put plaster on it and some bounding agent to attach the repetitive elements https://i.pinimg.com/564x/34/e4/04/34e4045e39debc... what can I use?

Topic by DIAGONALLIS   |  last reply

Equalizer for phono input to amp

Circuit for converting an MP3 player output to input for a phono input on an amp.

Topic by knorrisster   |  last reply

Why these relay issues?

In my PCB ,AC voltage is passes under the relays(R).. relays too become heat up.

Topic by sforsajith   |  last reply

Diy o-ring with glue-gun

For emergencies, but not only: make your own o-ring. use a hot glue gun and some soft glue-stick. look for a round object more or less the size of the o-ring you need. form a steady bead of hot glue around it. wait for it to set. peel it off. if necessary: smoothen down the edges somehow (sanding-paper, file, etc). feedback appreciated. thank you.

Topic by la xerra   |  last reply

Need Help in Building DIY LiFePo4 battery pack

Hello all, my wishes to everyoneam very new to this Electrical, Batteries and DIY, with the help of google i can gained little knowledge with that i could able to gather products to build my own electric scooter (1500W 60V HUb Motor and 60-72V regenerative controller with Daly LiFePO4 60V 45A Comm BMSactually am planning to Build 60V 36Ah LiFePO4 Battery Pack Using 19S6PBattery : LiFePO4 32650 3.2V 6Ah BMS : Daly LiFePO4 60V 45A Comm BMS Controller : 60-72V 1500W 35A am confused when times comes to assemble the battery pack, pls help and guide me with appropriate diagram or chart for 19S6P pack, help me how to connect batteries in series and parallel along with BMS so that i can build my first battery pack with out no mistakes Do i have use capacitors while connecting batteries, if so provide me the type already bought the battery tab spot welder from my friend for reference i have attached pictures of the products i mentioned and bought already please don't mind if i asked too much help/suggestions, want to make my own DIY battery pack by learning ad gather information about battery pack and build one one in perfect way Thanks in Advance

Topic by tejeyes 

Be your mechanic

Hello to all the magnanimousStudent professors and those who work in their own businesses Do not be tired of your loved ones. My name is Amir 48 years old and I have almost 32 years of experience in mechanical testing of cars in Tehran. I'm very interested in electronics and I repair almost 70% of my belongings But I did not attend classes in any classroom that I learned early. I'm glad to be among you I'm also happy to be in touch with mechanical questions Thank you

Topic by aryyyya1349   |  last reply

Home Page Images

The images for "Explore Projects" on the home page never seem to change. Repeat viewers could be excused for thinking that nothing has changed on Instructables between visits.How hard would it be to update the images on a daily basis ... using perhaps a random function?PS: This post is likely to be missed by viewers in other "Categories" and "Channels" as the posting options are too restrictive.

Topic by lingib 

Wordless how- to videos.

Https://m.youtube.com/watch?v=r0oX4I11BMc This is not my video, but I thought it was pretty cool. I really like some of these wordless how to videos. I suppose that it assumes a certain familiarity with the processes from anyone who would do these projects. Yet, if you don't have a familiarity with welding for instance, you probably wouldn't do this project anyway. Any other good videos like this one?

Topic by Toga_Dan   |  last reply

Calculating my DC motor

I'm not sure on how to calculate the things I need. Please help!!!!Pulley Radius- 5.85mmMass(load)- 0.2334 kgVolts- 9VCurrent- 0.096ASpeed-112.4rpmForce-?Torque-? Power-?Power Out -?Efficiency- ?

Topic by hj212121   |  last reply

What is going on? I want to see ALL the instructables, not a "homepage"

What is going on? I want to see ALL the instructables, not a "homepage". Stop messing with what works.

Topic by carlos66ba   |  last reply

Author Spotlight Interviews: Nominate an author!

We recently began a new round of author spotlight interviews. For the first interview, we chose to reach out and chat with Nikus, who recently won the grand prize in this year's Epilog Contest. You can check out our interview here: Author Spotlight: NikusThese interviews are a great way to learn a little more about individual contributing authors here on Instructables, and see what makes them tick! Is there someone who is an active author that you'd be interested in learning more about? Now's your chance to nominate a fellow author. There are no set requirements to be eligible to be nominated. But generally, we're looking for authors who've shared a good handful of high-quality projects, which made a notable splash within the Instructables community.And yes, if you're feeling bold, you may certainly nominate yourself! : )

Topic by seamster   |  last reply

Can't access my Inbox on Instrucables

Is anyone else having issues accessing their inbox on the site? Every time I try to open it it takes me back to the home page. The issues been happening for awhile now.Anyone know a fix or how I can get into it?Cheers

Topic by lonesoulsurfer   |  last reply