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Throat Problems - Scope Results - cause? - Diagnosis

       Some of you have probably seen my other 2 OLD forum topics, but if you haven't, I will explain it to you here. I have been having BAD throat problems for a few months now. Since I was about 9 I had food getting stuck in my throat. So one day, I was eating lunch, and food got stuck, slid down my throat and into my wind pipe. I started choking and couldn't breath. After that dramatic incident, I noticed a new symptom. I physically could not swallow. And on top of that I had an old symptom: heartburn. So I go to a doctor. He says I would have to get a scope.        So THIS is where the update begins. It was early September. I go in to get a scope. I wake up with the memory spam of a goldfish. So my family and I wait a while to go to the doctor for the results. So I go to my appointment where my doctor explains what is going on.                   ALL THE WAY DOWN my throat I have ulcers. Thus, around my ulcers they swell up, causing the difficulty swallowing         There are these things that MOST (not all) people have called esophills. I cannot find any info on these things so I will explain them to you instead of a link. These "esophills" are basically cells in your throat that react to allergies. They could swell up, itch, burn, etc. Well, mine swell up. The average person has about 5. I have 21.                      After explaining these things, my doctor says I have Eosinophilic Esophogitis (http://en.wikipedia.org/wiki/Eosinophilic_esophagitis) and says I have to get an allergy test.          Pardon my french in this paragraph....I go to see an allergist. He says to wait in the room for a few minutes until this hot girl comes in. She takes these blue pointy things and pricks me with them as liquid comes out. So she walks away, and we wait. 2 of the pricks start itching like hell. The doctor comes in, and says those two pricks are samples of corn and apples. Apples? No biggy. Corn? Damn...........why is that bad? Things that have corn that I was banned from: Soda, chips, pretzels, cereal, cereal bars, bread, and hell of a lot of other things.         So I don't eat ANYTHING with corn for about a week until the blood test results come in. About a week after the allergist appointment, he calls and says corn and apples came out negative. So I could go back to eating things with corn.        Tomorrow (10/4) I have to go get ANOTHER allergy test by taping food to my back. Hungary? Just rip the food off my back. Thanks for reading! C'ya will I go cry in a corner /sarcasm  

Topic by Flumpkins    |  last reply


why cant i watch videos on this site??

When ever i click the video button or watch videos on this site it just comes up with a wite box. and when i click the blog butten and try to watch videos it says there was a problem loading this video can someone help me!

Question by 2hot2hack    |  last reply


Basic electrical engineering question Answered

Although I can carve my way through data and can tell you a lot about how data is stored on various mediums, I am not the best electrical engineer, but I still do some projects for fun. I have a project that I am working to help a friend of mine who works in a climbing wall.  They had an existing siren at the top for the kids that someone broke, and wanted to switch it out to something that they could put custom sound effects on.  I happened to think of the 9V recording module at Radio Shack (http://www.radioshack.com/product/index.jsp?productId=2102855#tabsetBasic), and proceeded to hack it to make it more usable for their needs.  I made two different parts to it: 1.  The recording module in a project box, and 2.  A momentary switch at the top of the wall to trigger the module.  I changed the microphone on the recording module to a 1/8 in jack, sent the speaker output to a better speaker (with an amp of course), added a record button to the outside of the main project box, and created a "triggering system" by soldering a separate wire to both 1 and 2 in the picture, and then shorting it whenever I want to trigger the sound.  It worked perfectly in my shop, but when I installed it, the test trigger on the ground works, but the switch on top of the wall does not work well... it only works intermittently.  The wall is 2-stories high, so figure a 22 foot run for the wire (and I don't remember what gauge wire I used... it was just something I had laying around... but figure cheap speaker wire). My first guess was that it wasn't getting enough power from the battery, so I switched it out to a AC-DC adapter instead of the battery.  I am still having problems, so I am guessing it is too much resistance due to the long run?  (Would you agree or disagree?)  If so, is there some type of amplifying circuit that I could use to overcome this?  The only other explanation that I have is that the momentary switch that I am using at the top is pretty old and could be going bad, but I wanted to check first and see what you EEs out there think. Thanks for your help!  :) Edit: I'm sorry I am so bad at explaining this... I have uploaded my attempt at a schematic for clarification. Edit: After installing a new switch, it did work a little better, but still not 100%; so I installed the relay, which solved the problem.  Thanks to everyone who helped!  :)

Question by thegeeke    |  last reply


Help with Stepper Motor and Slip Ring

Hi All,    I need to figure out how to get power and control signals from a stationary computer / PIC into a series of subsequent rings via rotating joints. Ultimately, what I want to build is a form of motorized gyroscope that can transmit power and control signals to the inner ring motors. - I'm using a Raspberry Pi 2 to control three Stepper Motors. - The motors are getting power from an old AC/DC wall adapter. - I currently have 3x NEMA 17 stepper motors     - Yaw Motor/Axis     - Pitch Motor/Axis     - Roll Motor/Axis - I've got 2x 12mm 12 8-wire slip rings that I hope can be used to send the control signals from the Controller to each motor. The problem is that I'm not entirely sure how to connect those components together, let alone how to connect them to bearings to minimize tension on the motor shafts. (I'm a software engineer, not an EE or ME.) An example of what I want to build is this:  https://www.instructables.com/id/Multi-axis-Phone-Stand-completed-Version/ ( However I don't need anything in the middle, I just need a way to control the rotation of each ring layer independently by the stepped motors ) If anyone can point me in the right direction it would be much appreciated, Mike C.

Topic by MichaelC87    |  last reply


How can I find new driver boards for my 5-phase motors?

I will try to summarize the problem: 1. I have a CNC mill sitting in my garage that won't work because the whole control unit including the motor driver boards is shot. 2. I can't buy new driver boards because I don't know what spec to buy 3. I don't know which spec to buy because I am not an expert on 5-phase stepper motors and don't know how to judge / measure / test them to find their spec. So the CNC mill is of type EMCO F1P (1984), and it looks like this (actual photos of the unit). The control box that comes with it houses an awesome (for the time) integrated computer based on intel x86 chips to convert G-Code into movement. I had fun digging around inside it and here are some details about that journey. Unfortunately its from 1984 and in deteriorating shape. After being adamant for years, I have since given up restoring the control, and the current plan is to simply focus on the the machine itself with motors, which luckily is in a much better shape. This means that I will buy new motor driver boards to drive the existing steppers and get a LinuxCNC kind of control to control them. It turns out that finding a 5-phase step driver was much harder than I first anticipated. It doesn't help that the motors are without a spec. I asked a question on the ee stack site previously for finding the specs for my motor here but I didn't get any meaningful answers. I also blogged about this with lots of pictures here. So to sum it all up, any help/advice is welcome on the following:  + How to measure/test the motors to find their specs and hopefully a matching driver board  + Which brand of board is good/bad/cheap etc.  + What to look out for that I would not think of as a beginner PS: I know I could replace the motors with cheap Chinese 2-pole ones and be on my way, but I really want to do this the right way, and maybe learn something underway!

Question by lennartr2    |  last reply


​HELP! Looking for mechanical engineering advice in building a multiplier/compounding gearbox for a hand crank siren project

HELP! I have a project I'm working on that involves making a hand cranked mini air-raid siren utilizing a 12v generator and a 12v siren. I've done a proof of concept rig where I direct wired the siren to the generator and then used a drill to generate enough RPM on the shaft to get the noise I want. Problem is, I'd like to make this entirely manual and will be adding a crank handle once I get the housing built...which means, I need a way to seriously up my RPM. I've done research into building multiplier gear boxes and compound gear trains and pinions and everything in between, but am going to confess that while I'm obsessed with DIY projects, this one is exceeding my engineering knowledge. I am at a loss for how best to approach this build. What ratio would you suggest? 40:1? 50:1? Does anyone have experience building gear boxes that would be ok emailing me with their advice? The input for my generator is a 20 tooth gear (please don't laugh if I'm totally messing up all the nomenclature...most of my life experience comes from writing and baking and a very short (failed) stint as an EE...this is a totally new world for me.) and I got this information from another sub: it’s a 3600 rpm motor so 60/sec. I think the fastest I would want to crank is 2/sec, so, 30:1 gear box sounds about right. With a nice long crank handle a 50:1 should also work nicely. 10:1 is too slow. Ideally (and this might be where it gets really tricky) I'd like it to all fit into a space that's about 5"X3"X3, not including the siren (I can run that further out, using the leads).I'm attaching a photo of the original proof of concept wire up that I did...and don't worry, I know there are exposed wires, I fully plan on isolating the wires, insulating the whole thing and installing the proper resistors. https://imgur.com/a/MaAR2PQ Here is a link to the generator: https://ebay.us/zgAoDQHere is a link to the siren: https://ebay.us/fEgahDThank you in advance!

Question by Tye Rannosaurus    |  last reply


Proposal for a Multitasking Robot

Greetings, I am a senior EE major at Polytechnic University. I spent most of my time working with robotics and electronics. I always wanted to enter one of these robots competitions but finding the time and funds was always the problem. Its really interesting that iRobot is deciding to sponser a few teams. After brainstorming I came up with a few robot ideas that I believed novel. Then I thought about it some more and came up with more ideas. Instead of narrowing them down I thought how great would it be if all of them could be made. That led me into designing an idea for an iRobot Butler that can do many tasks. The idea is to create a modular robot that has the ability to dock with its base station and perform multiple tasks with different specialized modules. The project I propose is to develop the modular autonomous docking system and several modular tools for the robot to utilize. These tools can be used for entertainment purposes or for human aid. Here are a few concepts 1) Mobile Music docking station and amplifier - You have a stereo system, great! Only down side is its always stationary so you have to blast it till the neighbors know the lyrics if you want to hear it everywhere in the house. With this kind of a docking station just come home plug it in and let the music follow you. 2) IRobot key fob (that thing that opens your car) - Why have robot if you can't command it when you need it. With a IRobot linked to some off the shelf electronics you could have it meet you in whatever room you are in. 3) Where's the remote? Who knows? But iRobot can help you out by using a embedded universal remote following the sony ir protocol. Just give iRobot a buzz and he could come in and change it to your liking. 4) Not so Clocky Alarm Clock - Clocky is a robotic alarm clock. It rolls off its nightstand, hides somewhere in the room and then starts to wake you by forcing you to find where it hid. With the modular IRobot when you go to sleep it can hook up with its Music docking station and do pretty much the same thing. 5) Life Alert System - Many of us have been hurt at times where we wished someone could come to our aid. If you are in a accident and unable to reach a phone, press on IRobot's key fob and him lock onto another tool which brings you a cordless phone module to call for aid. The Docking Station The docking station for the robotic butler could be tracked using the same method as the self charging station. In order to remove platforms or add them a servo would be placed on the iRobot which would lock or unlock the tray. To maintain electrical connection between the two trays an array of spring header pins could be used. There are many great robotic ideas out there for the iRobot however the expense for one robot to only do one thing is pretty great. In order to compensate for the overhead expenditure a multifunctional robot with inexpensive and optional tools is a possible solution to suit home needs. This way all of the design entries can be utilized. Regarding my qualifications, I taught for three years as a teaching assistant to a freshman engineering course. My most recent completed project is the development of a chemical model car experiment and an Autonomous Underwater Vehicle design project for freshman engineering. Both of these projects underwent a rigourous amount of work and will be shown at the American Society of Engineering Education 2007 conference.

Topic by cooblades    |  last reply