Directional SPeaker

I saw a youtube video of a guy who built his own directional speaker (actually I remember it as a directional megaphone as he would talk into it, and it would target a person). I was wondering how easy it would be to do this? Can we build one with household material? Thanks for being awesome guys!

Posted by teamcoltra 9 years ago  |  last reply 3 years ago


shaft direction indicator?

Does anyone know an easy way to get/make a simple device to determine the direction of a spinning shaft?  It must give some logic (5V) signal, NOT encoded in any way.  Just +5 if CW or 0 if CCW (or backwards, or 3.3V, or whatever else, it doesn't really matter).  However, it must not A) require any digital controller (no arduino, ATtiny, PIC, computer, raspi, etc.) B) have an "encoded" output, or gray code C) have a large "dead band" where it still indicates CW but it's actually spun a tiny bit CW (or vis-versa).  Must be under 3-4 degrees D) require  the shaft to spin quickly E) be expensive.  This is a prototype for an ANALOG mill D.R.O., so I don't want to have to spend ten bucks on one part that I have to buy several of, plus the other parts.  Its a 1/4" threaded rod, but can easily be adapted to whatever else it needs to be.  The device needn't be small, and I will have a 3D printer avaliable (or at least a mill). 

Asked by jduffy54 5 years ago  |  last reply 5 years ago


Can I reverse servo direction in Arduino?

On my robot, both servos move clockwise. Is there any way in the  Arduino Environment to reverse the direction of one, to make it move counter-clockwise? 

Asked by DELETED_afw11 8 years ago  |  last reply 8 years ago


Compass on a chip

Does anyone know what I need to have a Compass on a chip? The idea is for a horizontal ring of LEDs with the northern LED lit. If the ring turns, the light will chase towards the north most point on the ring. I've found single and dual pole compass chips, but I admit a lot of ignorance about chips in general. Anyone have a shopping list for such a project?

Posted by catalyst 10 years ago  |  last reply 9 years ago


handheld direction finder

Hi - I'm looking for a project to build a handheld direction finder.  I would think you could do this using radio frequency.  Basically, I'd like two parts: the finder and the findee.  The finder would indicated the direction to the findee and that's it.  Not sure exactly what you'd call that... Thanks!

Posted by stevieruns 7 years ago  |  last reply 7 years ago


Why does my computer fan keep swiching direction?

Im trying to power a computer fan with batteries for a project. The fan wasn't turning so i tried upping the voltage. Ive tried one two and tree 9 volt batteries in series to make it turn. It worked best with two but the bizarre thing is that ever second or so it stops and sometimes switches direction. the fan has 3 leads red white and black. im powering red and back is ground the whit i think is a fan speed information wire of some kind. im not really sure. Any one have any ideas?

Asked by pineapplenewton 7 years ago  |  last reply 7 years ago


illuminated prayer carpet?

hi everybody i have a project to build a prototype so i need help if somebody could help me i could pay for this help cause i wanna produce it so my need is a illuminated prayer carpet based on  electroluminescent phosphor printing technology. the objectif it s to build a carpet who illuminated when its the right direction could somebody help please thanks

Posted by hkahil 8 years ago  |  last reply 8 years ago



How can I turn rotational motion 90 degrees?

I want to connect a horizontal, spinning shaft to a vertical shaft so that the first shaft will spin the second. Does anyone have any suggestions other than a gearbox or pulley/belt arrangement?

Asked by rogers236 9 years ago  |  last reply 5 years ago


Reversing Direction of Power Tool

It would be nice to be able to reverse direction of angle grinder, mototool, and similar tools. Sparks may be flying toward ones face in certain positions. The tool also may also tend to kick due to wheel direction. These tools arent made to reverse. How can one change this?  How can one keep the wheel from unscrewing and flying loose once the motor is reversed? 

Posted by Toga_Dan 3 years ago  |  last reply 3 years ago


Controlling servo direction with arduino Answered

So, I'm trying to control two servo motors for a robotic arm. I can't seem to figure out how to make two servos go opposite directions at the same time. This is needed as I have two servos facing opposite directions driving the same beam (If they're told to go the same direction, because they are facing opposite directions, they'll rotate opposite directions). Currently I'm using this code to rotate them both: for(pos = 0; pos < 180; pos += 1)    {                                    myservo.write(pos);                  delay(15);                        } and then using the same code, only replacing the top part with   for(pos = 180; pos>=1; pos-=1) to return to the original position. How do I make both servos go opposite directions though, so they can both be used to lift a beam at the same time?

Asked by 0xCyrusx0 9 years ago  |  last reply 8 years ago


is it possible to determine the direction a motor is spining by attaching a comparator to both leads?

The motor is not being powered with electricity it is being spun by hand. and if it is possible how can I determine the speed.

Asked by evilmadscientistman 9 years ago  |  last reply 9 years ago


Which Direction Does She Spin?

Check out the optical illusion below. Since the figure is totally black, there's no depth- you can see her spinning either clockwise or counter-clockwise. Which way do you see it first? Try reversing the spin direction- moving your finger in a circular motion at the rate of rotation can help you reset. How easy is do you find it to swap perspective? Does it make your brain hurt?

Posted by canida 11 years ago  |  last reply 8 years ago


would it even be worth my time to make an ible that makes a yagi antenna have not seen a lot of radio lovers on ibles? Answered

I found a really cool way to make a yagi direction finding antenna but i have not seen much interest on the site about radio operations

Asked by acidbass 8 years ago  |  last reply 8 years ago


Removing potentiometer and making a direct connection?

Want to remove those potentiometer ir order to attach a RsbryPie 3 heatsink to make the IC cool. IT'S a PAM8406,and on it's max load it's getting really hot. So have to apply a heatsink. So is there any​ way to remove those potentiometer and connect those line directly, i mean I'm newbie in this thing. So need some help, thanks in advance.

Asked by Sayan_trex 1 year ago  |  last reply 1 year ago


Direction Lens?

Is there a lens that takes all the incoming light and sends it out in one dirction

Asked by jj.inc 8 years ago  |  last reply 8 years ago


run car radio direct from battery

Hi ppl, I'm new here,been looking and d.i.y.ing since i found it. I have a question for any1 that has done this b4. I have a car radio, I have a battery, I have speakers, I have a shed to put em in, but how do I connect a car radio direct to a 12v battery? I have wired old ghetto blasters up to it, blown em all up like, so this 1 HAS to work lol. Any help appreciated, but would love diagram lol. Thnx ppl.... P.S. I might also need to know how to wire up the speakers.....

Posted by metalmark 11 years ago  |  last reply 11 years ago


Whistling blade on wind direction weather vane

I have a propeller with four blades that acts as a wind direction weather vane. What I would like is for the propeller to make a whistling noise when it is rotated by the wind. Someone told me if I put a small hole or a slit in each of the blades it will make a whistling noisy which should change with wind speed. Can anyone tell me what size hole/slit I would need? Also at what angle would the slit have to be? Or can you tell me any other way to get a whistle from the blades when the wind is blowing? The blades are metal and about 200mm long (400mm overall diameter). Thanks for any help. Lou

Posted by LouL 10 years ago  |  last reply 7 years ago


Whistling blades on wind direction weather vane

I have a propeller with four blades that acts as a wind direction weather vane. What I would like is for the propeller to make a whistling noise when it is rotated by the wind. Someone told me if I put a small hole or a slit in each of the blades it will make a whistling noisy which should change with wind speed. Can anyone tell me what size hole/slit I would need? Also at what angle would the slit have to be? Or can you tell me any other way to get a whistle from the blades when the wind is blowing? The blades are metal and about 200mm long (400mm overall diameter).

Posted by LouL 10 years ago  |  last reply 3 years ago


How to make a direct microphone to speaker circuit?

Hello all, I recently wanted to develop a circuit which picks up voice signals from a microphone and outputs it to a speaker. As I recently started learning to build circuits, I was hoping to get a few inputs and tutorials on how to build one in a step by step manner. Please help by giving instructions and not a circuit diagram as I am still learning. Thanks for all your help! Regards, Microtest

Asked by Microtest 4 years ago  |  last reply 1 year ago


Best Type and Source for Omni Directional Wheels?

I am currently in the process of compiling a shopping list for an omni directional robot a team and myself are planning to put together. For this, wheels that go both forward/backward and left/right are needed. From what I have found, there are two variations: Omni and Mecanum wheels. Due to our design, we will be needing Omni style wheels.  However, doing some research, I haven't been able to find much of a selection! So far, robotshop is the only website that actively stocks them, and they sell two brands/types, one being VEX.  Is there a generic name for these types of wheels? Where would I be able to find more/a different source for them? Why are they so expensive? If you've used an omni wheel, what type/brand was it, and what was your opinion on it? The big problem is, is that we need to mount the wheels onto 5mm stepper motor axles. Half of the wheels I found on robotshop had square bores, and the other half used an interchangeable hub, none supporting a 5mm axle. Any ideas as of what to do here? We would like to get four wheels, preferably for less than 50$.

Posted by RocketPenguin 1 year ago  |  last reply 1 year ago


Rotary switch w/ direction based contacts??

I'm looking for a specific type of switch... I believe that it must exist, but I have never seen it... I need a rotary switch, where each clockwise "click" (partial turn) makes one circuit momentarily, and each counter-clockwise turn makes a different momentary conection... example with two light bulbs ( L1 and L2 ) connected to each direction of travel, respectively: If you rotate the knob one "click" (say 15 degrees) clockwise, L1 flashes for a moment, as the knob is in motion. if you continue clockwise, L1 will flash at each "click". If you rotate the knob one "click" counter-clockwise, L2 flashes for a moment. if you continue counter-clockwise, L2 will flash at each "click". There is no center-point, so any clockwise travel corresponds to L1, and any counter-clockwise travel corresponds to L2. does anyone know where I could get a couple of these??

Posted by gschoppe 11 years ago  |  last reply 3 years ago


Stepper motor vibration/lockup with driver? Answered

I am trying to get a stepper motor to turn using a StepStick driver from Botronicz. I have gotten the driver to work once before, but now it has decided not to work. I have wired my stepper motor (Model STP-42D3018) according to any specs I can find online in a bipolar connection, but when I fire it up the stepper only sits there and vibrates. Or misses steps (depending on voltage). A few other times I had it also where it would step one direction for I think a single step and then step back the other direction. It is really bothering me because I have tried multiple other wiring combinations and have not gotten any of those to work. My current setup is exactly like this (I have checked numerous times). I have also tried changing the vmot supply voltage and current limit, as well as the current limiter pot on the board itself. If anyone can help it would be greatly appreciated! Sincerely,  A907

Asked by astroboy907 5 years ago  |  last reply 5 years ago


Apparently no direct relationship between Brix and water content???

Could anyone explain to me why there is not a direct relation between the Brix scale and the water contents scale on my honey refractometer? At the low end of the Brix scale (60-70), the match is perfect, but not at higher Brix. I suspect this has something to do with the fact that there is a non-linear relationship between sugar concentration and density. It would, however, be very nice to know the proper theoretical background... :-) Any help will be greatly appreciated, as I have been unable to find any information at all on the web. Thanks!  Best regards, tome

Asked by tome 8 years ago  |  last reply 8 years ago


I want to use a very simple circuit to start, stop and reverse the motor. Does anyone have any idea of such a circuit ?

We are currently doing a project to retract a certain beam and to extend it. We require a switch to start the motor to extend the beam, stop it and retract the beam when needed. The stopping part would be automatic. The start can be activated from a switch and the reverse switch would be connected to our previous circuit. We really need help for this motor circuit.

Asked by rukesh 9 years ago  |  last reply 9 years ago


Why would I need to know the 'extrusion direction' of Lexan?

I bought a small square of Lexan (sheet polycarbonate) to experiment with and noticed on the clear, protective laminate the words: "extrusion direction" and an arrow. I will most likely use this sheet for thermo -forming, but would like to hear any thoughts on how the extrusion direction might affect drilling, cutting, etc. Thanks, Marshall

Asked by redplanetcorridor 7 years ago  |  last reply 7 years ago


how mobile phones convert Aternating voltage to direct voltage?

There is no big transformer in a mobile phone charger but still it is able to convert A.C to D.C though it is small

Asked by deepakmurali 6 years ago  |  last reply 6 years ago


Can I use the battery charger as a direct power source?

I am making an automatic button presser for my Nikon CoolPix 4800 camera so I can make time lapse videos.  My problem is that I don't have a power adapter for my camera.  If I connect the battery charger directly to the battery slot in the camera, will the camera run safely? There is a jack on the side, but it's a strange jack that I have never seen before.  The jack is listed at 8.4V. The charger has an output of 8.4V and 600mA On the bottom of the camera, it says: 8.4V ---- 0.4A 6V -----0.6A Then, strangely, the rechargable lithium-ion battery says 7.4V, though it could be a typo. So, if I connect the terminals on the battery charger into the terminals in the camera where the battery hooks up, will it run safely? Thanks!

Asked by Wehrdo 8 years ago  |  last reply 8 years ago


Direct Current Solar Powered Homes- Can a strictly direct current environment be used for a house? Answered

How to power a home with on direct current colar power.

Asked by erick829 9 years ago  |  last reply 9 years ago


Is it better to put compost bin under direct sun or under shade?

I have several compost bags (ex flour). I put them on shade. But I just read from the web that compost works better under direct sun. My question is it better to put my compost bags under direct sun or just keep tem away from direct sun? Could you please give the reasons also. Thanks

Asked by kelana 9 years ago  |  last reply 9 years ago


How to control DC motor speed, distance, and direction through Bluetooth???

Hello all:  Absolute electronic noob here looking for advice.  Thank you all in advance for your input.  What I am trying to make is a small inexpensive rechargeable device that will take small various objects back and for at variable speeds all controlled via Bluetooth.  “Android/IOS.  I would like to keep the device no larger than 6 to 8 inches but, if necessary can go larger.  I am hoping I can control the speed as well as the distance the objects travel via Bluetooth. As far as direction I would like a set back and forth stop point.  At this point the entire project is in my head.  I apologize for my electronic ignorance.  Again Thank You.

Asked by DougB53 2 years ago  |  last reply 2 years ago


Can UART or FTDI serial work with communication in only one direction? Answered

Can UART or FTDI serial work with communication in only one direction? or no? Or is there no universal protocol (as in UART only defines the type of connection, not what data is sent though it)  I am building a quadcopter and was thinking of using one of the 2 audio channels to send serial data down one of the spare channels, and the other channel is just connected to a microphone to 'listen' to the noise of the props. I have 2 major concerns with this method: Will the frequency response and bandwidth of the audio channels be high enough to carry a 115200 bauds signal, or at the very least a 9200 baud signal? and the original question; do I need a 2-way connection for information from the UBLOX GPS or multiwii output? If yes, then i guess the only way to get telemetry is to get one of those 900MHz transmitters, yet another board that I will have to deal with.

Asked by -max- 4 years ago  |  last reply 4 years ago


is there directions for making pot scouring pads out of tooling?

 

Asked by mmlara 8 years ago  |  last reply 8 years ago


in house/property phone to phone direct line

Anyone know of the easiest way to make a permanent phone to phone direct line. As in a phone from the back shed to the house. I want to be able to pick up the phone in the house or shed and have it ring on the opposite phone. any idea's?

Posted by chaoscampbell 11 years ago  |  last reply 11 years ago


Does anyone have directions for a three color paracord bracelet.?

Asked by deerhorn 7 years ago  |  last reply 7 years ago



Does anybody know a way to link two networks wirelessly (with directional antennas) where more than one jump is needed?

By "more than one jump" I mean that I want to send a wireless signal from my house via a directional antenna to a device that then repeats the signal down to the destination (also via directional antenna). I thought of just an average repeator, but I haven't seen one that works with directional antennas. Any Suggestions? Thanks, -Double_G

Asked by double_g 9 years ago  |  last reply 9 years ago


coverting 24volt rechargeable lawn mower to use direct AC wired connection.

I am not able to start a gas mower and so I utilize a very old electric mower. A friend gave me a black n decker rechargeable 24 volt lawn mower, no "key" and no charger.  I was pondering putting an AC/DC power converter on the mower body and then using an extension cord to power mower. But concerned about running motor direct from converter. I would of course by pass the battery pack and go direct to motor because there are always warnings about not running an appliance while charging. So thinking along these line took cover off motor body and off the wiring in the handle.  Upon inspection except for the wires going to the batteries from the motor, the motor itself looks like the electric motor in my old direct electric lawn mower! My question is: Would it be possible to directly wire AC power to the motor of this DC powered motor? I am not an electrician but understand some basic principles. After reviewing specs on B & D's webs site know that there is some type of inverter built into the battery pack. I'm assuming it is to convert AC to DC for charging them. Could I wire directly to it then to motor and not use the batteries? I survive on a very low fixed income and can not afford to buy a replacement charger and needed "key" (connects wires to make it run). I do have wire and soldier and a desire to make it work. Any advise would truly be welcomed.  Otherwise I will proceed with my inkling of an idea and tell you how it goes or not! thank you.

Posted by nitajayne 5 years ago  |  last reply 2 months ago





how to make a telephone work from play house outside to kitchen?

I was once told about a father who was able to set up a direct line from the kitchen to the wendy house. So the child could have a hot line direct to mum.

Asked by 9 years ago  |  last reply 9 years ago



silk screen machine

Im looking for plans on building a silk screen machine, can any one direct me in the right direction. thanks...........Camtech

Posted by Camtech 11 years ago  |  last reply 11 years ago


direct nodeMCU control?

Hi guys this is my first attempt on automation using the nodeMCU lua ESP8266  My goal is to control the gpio via wifi without connecting the node to my home network it should dependent  I have found e bunch of code but it has to be joined to my homework thanks

Asked by Conwyn' 1 year ago  |  last reply 1 year ago


DIY Virtual Reality Omni-Shoes

Since buying an oculus rift, realizing the limitations of movement. I've been researching all the different types of Omni-directional methods of moving in a virtual enviroment. Infinadeck seems to be the best option but it's probably too expensive for me.Vortrex looks a nice concept, I would like to try and see what it feels like having my forward motion cancelled out. By building my own conveyor belt shoes, there is a video on youtube demonstrating powered shoeshttps://youtu.be/C5hPyHxrz94The prototype above, uses roller skates powered by two motors with flexible shafts This is similar to what I want to replicate. I dont mind being tethered by power cables.I'm trying to put together a list of the main components suitable for operating under these load conditions. What motors/flexible shafts are a good choice for this application?.

Asked by xorcyst 11 months ago


can i boost wifi with outside hd directional antenna?

I have a cricket modem and a outdoor hd directional antenna can i somehow run coaxial cable to modem and get a better signal? If not . what is the best way to go about increasing signal strength, while being cost effective?

Asked by 9 years ago  |  last reply 9 years ago


Synchronous AC110V Motor Question

I have a small AC synchronous microwave motor that I want to use for a project. The problem is that even though it says CCW/CW, which i take it to mean counter clockwise and clockwise, it randomly seems to choose which direction it wants to turn rather than me reversing the current to change the direction. What makes this motor randomly choose a direction? Is it some internal component that randomly decides it's direction? Basically, is there a way I can make it go the direction I want? If not, can someone point out a small size motor type that is cheap and has a lot of torque? Thanks to anyone who replies!

Posted by rodneykristy 6 years ago  |  last reply 6 years ago


single phase ,brushless direct current motor.

Does anyone have the schematics for a VERY SIMPLE, (LIKE ME) single phase brushless DC motor.

Asked by ianrbell 9 years ago  |  last reply 2 years ago


Diffuse or direct bulb light for an area.

Http://img.alibaba.com/img/pb/891/178/257/ws_transfer_pic_7849270_1.jpg Say that you had a 5W led and you wanted to light a small room, would it be better to use a bulb with a clear / no dome or one with a diffuse / frosted dome? Would there be a big difference between the two?

Posted by Full Metal 4 years ago  |  last reply 4 years ago