Sensors convert a physical quantity (e.g. temperature, pressure) into an electrical signal.
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1answer
32 views
OneWire DS18B20 on mighty 1284p can't find my sensors, same sensors work w/ Duemilanove
I have uploaded the DS18x20 Temperature example sketch (unaltered, except I tried multiple pins for the I2C communication) to my proven Duemilanove and my ...
4
votes
1answer
91 views
How can I use a generic doorknob as a capacitive touch sensor?
I would like to use a generic doorknob that's installed in a typical wooden exterior door as a capacitive touch sensor. I have found various references for the circuit, but I have some questions about ...
2
votes
2answers
64 views
How to connect sensors to an Android device?
I need to build a device, which measures several parameters (body temperature, conductivity and pulse) and transmits them to an Android mobile device.
The system has following parts:
The sensors
...
2
votes
2answers
135 views
Expanding Range Of Analog Values From Temperature Sensor
I'm trying to build a temperature controlled relay module with an ATtiny45 ( Arduino UNO R3 as ISP ) and a NXP KTY81-222 Temperature Sensor.
The temperature range i want to monitor is 20°C to 30°C.
...
3
votes
0answers
63 views
Charge mode piezoelectric signal conditioning
I have a charge-mode piezoelectric dynamic pressure sensor (datasheet link) that I want to read a signal from. If you look at the datasheet it says the sensor outputs are in a balanced and floating ...
1
vote
0answers
61 views
Sensing pressure from 4 tanks, using 1 pressure sensor [closed]
I'm tryng to read from 4 water tanks pressure/level, each containing max 10liters.
For this goal and for minimizing the costs, I was planning to use:
1 pressure sensor (5V, digital or analog, ...
-1
votes
1answer
41 views
interfacing a transducer to a pic16f877a
I have a pressure transducer with an out put of 4-20mA and having problems in interfaceing it with a pic16f877a micro-controller
4
votes
4answers
189 views
Ideas for a cheap, simple, common temperature sensing component?
I'm looking to make a device to regulate a heater to maintain 100-110 degrees Fahrenheit in a small, moderately insulated container. Specifically, I'm wondering what I might have in my parts drawer ...
3
votes
2answers
68 views
Heat Activated Alarm
I am working on a project in which I have to simulate a heat activated alarm. I have attached two images. One of which is a Proteus circuit image that i have made. When i start its simulation the ...
2
votes
1answer
76 views
Reversing a .5-4.5V analog sensor output to 5V-0V
I have a pulse width modulation (PWM) control board that uses a 0-5V input via a potentiometer to control a DC motor speed. As I understand how this works, the potentiometer goes from 0% PWM at 0V to ...
-2
votes
0answers
36 views
looking for philips humidity sensor eagle .lib file [closed]
I'm working on my first eagle project, I want to use the philips humidity sensor 2322 691 90001.
http://www2.informatik.hu-berlin.de/~hochmuth/bvp/humidity.pdf
My problem is that I can't find this ...
1
vote
1answer
44 views
MQ137 Ammonia sensor - Pins not labeled
I recently purchased an MQ137 Ammonia sensor and breakout board. Unfortunately the item came with the two parts separated with no markings as to the orientation. Can anyone advise on the pin layout?
...
-2
votes
0answers
60 views
Which kind of sensors should I use to mimic a reference? [closed]
My project for this summer will be to make a robot arm that does a 1:1 mimic of one of my own arms. I'm at the very beginning stages of design and am conceptualizing what it will be and how I will ...
1
vote
1answer
66 views
Suggest some methods for measuring AC current
I need to find a method of doing so without consuming much space in PCB like in the case of current transformers. The circuit must be able to measure upto 15A of AC current(RMS).
0
votes
1answer
70 views
Interference beetween ADC samples with XBee and photoresistor
I'm using an XBee serie 2 module for sampling the values of three sensors, a photoresistor (LDR) a moisture sensor and a temperature sensor (LM35). When there is no brightness the photoresistor has ...
0
votes
0answers
58 views
Arduino Compatible CO2 Sensor [closed]
I am looking for a relativity inexpensive CO2 sensor that will work easily with an Arduino. I have done some research and only found one real option, and it looks like some sort of an amplifier will ...
2
votes
2answers
135 views
The influence of a potentiometer on photo-diode bias
I have a sensor which I have connected to an Arduino via SerialPort to get data readings.
There is a "screw potentiometer" (It's a screw that changes resistance which affects the output voltage).
If ...
3
votes
1answer
94 views
Temperature current source using a LM35
Anyone care to explain how this piece of circuit work?
I already build it and it works wonders but I can't figure it out.
0
votes
3answers
83 views
Modifying a digital LED thermometer kit to drive larger 4" 7-segment LEDs?
I'm interested in building an LED digital thermometer with 3 or 4 large 4"/100mm 7-segment LED display digits (for example, Kingbright SA40-19EWA). There are plenty of kits available which come with ...
8
votes
2answers
239 views
Collimating a sonar beam
Wondering if anyone is aware of a way to cause an ultrasonic proximity sensor to be modded, such that, it's forward line-of-sight range remains unaffected, but it's angular spread is reduced, somewhat ...
7
votes
3answers
299 views
Circuit works on breadboard but not PCB
I have a fairly simple circuit that works perfectly on the breadboard, but I am having a lot of trouble transferring it to a PCB. I am seeing very strange behavior which lies outside of my current ...
0
votes
1answer
252 views
Water level: BIG capacitive level sensor with steel bars?
So I want to measure water level under a bridge, or inside the city drain.
Would it be possible to run two long (4 meter) metal probes, each one enclosed inside a PVC pipe, and placed one next to the ...
1
vote
2answers
71 views
Recommended Sensor? Distance - High Heat & Dusty
I'm after a sensor and I'm wondering what would be the best type for the following.
Requirements -
Accurately measure in the 5-10mm distance range, +/- 1mm.
Sense small undulations in a surface ...
2
votes
1answer
92 views
Can I electronically trigger a PIR motion sensor?
I would like to trigger a PIR sensor using an infrared LED. Is that possible? My goal is to simulate motion in front of the PIR, when there otherwise is none. I tried using a handheld remote ...
1
vote
2answers
60 views
How can I make a motor stop when the output of a PIR sensor is below a threshold?
I will attach a PIR sensor to a motor and i want the motor to stop turning when the output of the PIR sensor ( http://www.rapidonline.com/pdf/61-1466.pdf ) is below a threshold. I also want the motor ...
4
votes
3answers
118 views
Is the Excitation Voltage of a load cell a strict specification?
When using load cells (or strain gages generically), is the Excitation Voltage spec provided as a strict minimum -- or is it just a recommendation which one can go below as long as one is OK with a ...
1
vote
2answers
94 views
Is is possible to produce a resistance that represents the average of two thermistors?
For example, if I want to connect 2 thermistors to a thermostat in a circuit and then return the average resistance between the two of them to the thermostat's ADC.
-1
votes
3answers
97 views
No previous knowledge of programming, considering electrical engineering [closed]
I am still at school and wont finish until 2015 but i have seen people control doors, toy cars etc with their iphones and i really want to get in to something like that.
I have a lot of spare time ...
-1
votes
3answers
137 views
tiny dtmf dialler [closed]
I would like to create a small dtmf dialler that connects to a telephone line and dials a single preprogrammed telephone number when a set of contacts closes, how easy is this and how small could this ...
2
votes
3answers
81 views
Wireless communications for distance estimation (RFID perhaps?)
What I want to do it is measure the distance between two points/ devices which are constantly moving apart or together. The value for distance isn't really required I'd just be looking to have an ...
2
votes
3answers
152 views
Simplest touch sensor for a copper surface
I'm looking for the simplest way to implement a binary on|off touch switch using a single pole. The touch surface is copper. The position or pressure of the touch is not needed, just simply:
On = ...
0
votes
3answers
113 views
A device that wirelessly, securely posts to a server in response to door opening: off the shelf or custom-make?
I am looking for an off the shelf component for a project I am currently working on. Due to the nature of the project I cannot go into much detail about the project itself, only give a high level ...
0
votes
2answers
148 views
I2C temp sensor and an Arduino wifi shield not working together
I am using an arduino wifi shield and a TMP102 with an arduino uno rev2.
With boards older than rev3 you have to add a jumper from the 3.3V to the IOREF pin for the wifi shield, see here: ...
4
votes
4answers
153 views
devices for measuring tension or detecting “slackness” in fishing wire
How might I go about measuring the tension in a line of fishing wire? I'm mostly interested in determining when the line is in tension vs when it's slack.
The application is a boat-mounted ...
4
votes
2answers
65 views
Xbee to act as wireless i/o extension
I want to have an arduino with an xbee (call it xbee1) connected to it and another wireless xbee (call it xbee2) communicating with xbee1. Then I would have DIO1 on xbee2 acting as a digital input and ...
0
votes
0answers
42 views
Arduino sensors for x10
I am wiling to begin my ride in home automation.
I realy want the Insteon ISY controller(that is x10 compatible) and some x10 2-way micromodules. But the project is realy complex and I need some ...
0
votes
2answers
629 views
Arduino controlled PWM PC Fan
I am looking at getting 2 Evercool EC8015HH12BP 80x10mm (4-wire) PWM fans. However, i am looking at controlling the fan speed with the arduino via the PWM pins.
I found the following diagram that ...
0
votes
0answers
99 views
Sensing salt concentration in air
I need to measure salt concentration in air (coastal). Any ideas how?
I would prefer to have result real time and it can be up to USD 2000.
5
votes
2answers
169 views
How to process voice commands using ATmega or Arduino?
For a project I need to start my PC using voice command. I thought to made up an voice controlled system to turn on my PC. As far as I know, when I press the turn on button-2 pin's on the motherboard ...
3
votes
3answers
121 views
Vibration Detection bronze keyed instrument
I want to be able to detect when a bronze key (Balinese Gamelan) gets struck by a mallet (hard wood) without effecting the keys vibration, so a piezo is likely out.
Example of the instrument:
Is ...
1
vote
1answer
60 views
How do I know what the right signal amplifier to use is in order to program a hall-effect sensor?
I am trying to look for a signal amplifier in order to program the sensitivity and offset of the A1362 Hall-Effect sensor.
Doing a simple google search reveals:
...
4
votes
3answers
138 views
Measuring the step length during walking
I would like to measure the step length during the walk and I am searching some ideas
to solve this problem.
I am not really an expert on sensors so I am trying to collect some information in order
...
6
votes
0answers
173 views
What is a good electronics kit for the everyday inventor [duplicate]
I am looking for a good electronics kit with lots of capacitors, trimmers, resistors, pots, diodes, transisters, leds and laser diodes, timers(like the 555), inductors ICs and common microchips, LOTS ...
4
votes
2answers
98 views
Connecting Analog Signals Between Boards
When you have a sensor with an analog output on one board, and an analog-to-digital converter (ADC) on another board, what's the best practice in connecting them together? For example, if you have a ...
0
votes
0answers
66 views
bmp085 output is little off
I have got this Bosch barometric sensor BMP085 and im trying to make library for ARM LPC2000 microcontroller. Basically i have everything running but my reading values are wrong. I have tested ...
0
votes
1answer
65 views
multiplexing 16 sensors
I need to read 16 color sensors(TCS3210) one after another. So I am thinking of connecting all the outputs to a single atmega32 i/o pin and selecting a sensor using a demux showing low on the output ...
1
vote
1answer
144 views
L3G4200D Gyro Sensor - Measuring Angle?
I am making an IMU for 6DOF which has L3G4200D 3-Axis Digital Gyroscope.
I've checked so many Blogs, Forums, Application notes and have programmed accordingly to get the proper reading/information ...
2
votes
2answers
305 views
Load Cell Amplifier AD620
I know AD620 is an old part but it is available at my place. I intend to develop a Load Cell amplifier. Load cell is 2mV/V. I am planing to use AD620 for it. Following are my calculations:
...
4
votes
2answers
140 views
Real time location sensor for following a kite in the air
In search of a new project I decided I want to build a kite which I can fly using my computer. For this I need a couple of things: a kite, an electro motor to steer the kite, and also a way for the ...
0
votes
1answer
124 views
Getting a incorrect voltage from a analog sensor
I'm trying to build a very simple thermometer using shift registers, 7-segment LEDs, and a LM35. The idea of the project is to learn more about shift registers and how to use them. What I've done so ...
