Questions on a set of equipment used to generate and transmit electromagnetic waves carrying messages or signals, esp. those of radio or television.

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0answers
20 views

Accelerometer output transmitted via Bluetooth [on hold]

I have a project in which I want to send the output of a standard(piezoelectric with analog output) accelerometer via Bluetooth to other devices. The sample rate of the signal that interests me is up ...
1
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1answer
57 views

Transmit electrical signal across human body [on hold]

Is it possible to transmit and receive an electrical signal SAFELY using the human body as a medium? For example, I would have a transmitter of some sorts in my left hand, and a receiver in my right. ...
0
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1answer
48 views

Timed Infrared or Infrared PWM Signals

We are trying to have a moving IR receiver pickup a specific IR-led for a range of IR-LEDs. The options we're looking at : Send and unique pwm signal from each different led, the moving object ...
0
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2answers
59 views

How to remove the static sound in an fm transmitter

Hi I have a school project and I used the schematics from this website for our FM transmitter. Its actually working but its hard to recognize the music being played because of the static, also does ...
0
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0answers
38 views

Transmitting data over Long range ,using a Low Power Circuit

I Have Been Designing a BOT That Would Travel Along the Pipeline And Detect Leakage Using Ultrasound Efficiently,And Locate The Position of Leakage Using A GPS MODULE using the Arduino,I have make it ...
1
vote
1answer
63 views

Boost a weak AM transmitter

I've made this simple AM transmitter: http://makerf.com/posts/fun_with_crystal_oscillators_part_3 The author of this circuit, claims that would be possible to extend the range of this transmitter ...
0
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0answers
100 views

Is wireless power transfer by induction at 60Hz possible, or does the frequency need to be changed?

I want to build a wireless power transmitter that works over a very short distance. Can I use my line voltage(120V at 60Hz) through the primary coil to induce voltage into a secondary coil about 1/4" ...
0
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1answer
16 views

Looking for a LED transmitter/receiver package(or group of components)

I am trying to design a system that utilizes 355nm and 370nm LEDs. I want to keep their intensity stabilized at a certain value, so I want to create a feedback loop. I am using these LEDs as ...
1
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0answers
48 views

How to convert laptop to charge wireless

I am wanting to charge my laptop using Qi wireless charging transmitters and receivers. Setup: The laptop battery is a Li-ion belonging to a Sony Vaio Flip 15A (output: 15v 3.17 Amp, input: 19.5v ...
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0answers
52 views

very short range wireless on/off switch [duplicate]

I am in need of suggestions for a wireless on/off switch for my project. I will be using it to trigger an LED and or a sounded alert but am struggling to find one that meets my requirements; It ...
-4
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0answers
50 views

transmitter and receiver switch

I need to build a wireless switch (preferably RF) for a LED and possibly trigger a sounded alert using a transmitter and receiver pair and it needs to have a range with a strict maximum of 2 meters. ...
0
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0answers
15 views

T/R switch for single element material thickness testing (-200V pulses)

Our non destructing ultrasonic inspection design now has two crystals, one for transmitting and one for receiving. We would like to have only one crystal for transmitting and receiving. This is common ...
0
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1answer
33 views

How to adjust or obtain different IR Transmitter's distances?

I would like to recreate a infrared concept used by in the vacuum cleaning robot's charging station. I would like to use 3 infrared transmitters all in same wave length and transmit a synchronized ...
0
votes
2answers
72 views

Understanding a simple crystal oscillator transmitter circuit

I've recently built this circuit: http://makerf.com/posts/mighty_simple_shortwave_transmitter It works on the desired frequency as you can see from this video : ...
0
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0answers
35 views

One Transmitter for multiple recievers

I need to track case pans at work, I would like to do so by using cheap 433Mhz receivers. My problem is we have up to six hundred case pans in the building at any given time. Will I be able to use one ...
0
votes
2answers
100 views

What technique can I use to focus a Bluetooth 4 transmission (or at least shield it)?

I'm actually trying to focus an iBeacon that uses Bluetooth 4.0 LE. These transmit in the ISM band from 2.4 to 2.485 GHz. Normally these things radiate in a spherical, or half spherical pattern, but ...
-1
votes
1answer
99 views

RF - separate transmitter and receiver antennas for half duplex

i was wondering why is it for just half duplex systems, don't we have a dedicated transceiver and a dedicated transmitter antenna. ok, just hear me out... assuming we are using grounded monopoles, ...
1
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0answers
53 views

Best transmitter and receiver for the job? [closed]

I am very much an amateur when it comes to this just to warn you. I am trying to build a device which will on the press of a button has a transmitter send a 6 digit code to a receiver, which will ...
0
votes
3answers
208 views

How to build a simple LED transmitter and receiver

I'd like the distance to be about 1/10th of a mile; less distance will be fine if that's easier to build. What tools and parts may I need for this? I have plenty of LEDs lying around and I have ...
0
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0answers
25 views

High level sensor protocols

We are developing a sensor gateway for industrial usage (a kind of internet of things transmitter). The type of sensors are slow frequency sensors with measurement intervals above 1 second (e.g. for ...
1
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2answers
47 views

What are the trade-offs of transmission bands?

If I were designing an RF circuit how do I determine what band the circuit should operate on? What are the trade offs? and why is the higher the frequency the lower range? It is quite un-intuitive for ...
0
votes
1answer
81 views

Questions about FM receivers and transmitters?

I have a test tommorrow on phase lock loops, AM/FM receivers along with several other topics. I need to understand this topic clearly before I take the exam to advance to the next schooling in the ...
10
votes
2answers
576 views

How does the plastic-tube inductor in this wireless transmitter work?

This single layer PCB (solder side shown here) is from an old fan remote: The inductor in the plastic tube is not connected physically to any components; however, the two loops of wire surrounding ...
0
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2answers
57 views

Peak-to-peak voltage of WRL-10534?

I'm experimenting with the 434 MHz RF Link transmitter (WRL-10534) from SparkFun. I'd like to determine the peak-to-peak voltage of the RF output, but I don't have access to an oscilloscope that can ...
1
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1answer
67 views

Wireless transmission power for multiple receivers

I have just started learning about wireless systems and for some reason I'm hung up on what I feel is a fundamental idea. Consider some transmitter-receiver pair with isotropic antennas. The receiver ...
0
votes
1answer
39 views

Replace LED by a Trasmitter

I need a wireless switch with capability to report current state, so I would like to modify a wireless switche like this, by replacing a current state LED by a trasmitter to get the state of current ...
1
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2answers
177 views

square wave carrier signal

I am having some trouble to put things together into one picture. Can a modulated carrier wave be a square wave? If yes then How? Because at resonant frequency at the transmitter, the current ...
1
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2answers
136 views

How would I measure distance with a transmitter/receiver pair?

I am looking to build a a device that can transmit/receive its distance from another device, with the other device doing the same up to 50 meters. Will using a fm transmitter and receiver with a ...
9
votes
4answers
489 views

How is it possible to have a 5W transmitter driving 50 ohms with a 12V supply?

So let's say you have a circuit, which generates a carrier wave at some frequency (let's say 27MHz) and it's connected to a 50 ohm dummy load (which I gather is equivalent to an antenna for circuit ...
1
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2answers
62 views

Distinguish between two ultrasonic transmitters

I want to have two ultrasonic transmitters emit signals to three receivers for measuring distances and relative position of the transmitters to the receivers. The distance between the transmitters is ...
0
votes
1answer
76 views

Orientation of ultrasonic receiver

I would like to use an ultrasonic transmitter and three receivers to be able to determine the position of the transmitter relative to the receivers. The distances to be measured are around 3-4 ft. I ...
-1
votes
1answer
407 views

What is the best and simple circuit diagram for a radio receiver to receive radio waves in Citizen's Band [closed]

I am building a two way radio system using the citizen's band in India. The transmitter is using a 555 timer IC clocked at a frequency between 26.957-27.383MHz to transmit AM waves. Can you please ...
0
votes
3answers
182 views

What's the relationship between samples and bits?

I was talking to a friend today that I have a transmitter which is capable of sending 128 samples/second. Note that each sample is a voltage level represented by a floating point decimal. He then ...
0
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0answers
245 views

Datasheet for Keyes IR Transmitter (KY-005) wanted

Can someone help me find the datasheet for the Keyes IR Transmitter (KY-005)? I know how the pins work, I just need to figure out its voltage drop and how much current should go through it. Thanks! ...
0
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0answers
40 views

Is this an antenna or an inductor or both? And does the wire length/core diameter matter?

I have a small transmitter, and attached to it is this device: However, one of the wires attaching the circuit board to to circular red device is broken. I figured that since I have it all taken ...
0
votes
1answer
353 views

Creating a home made ultrasound transducer

I don't know how ultrasound transducers (transmitters) are made, is it possible to create a home made ultrasound transmitter with a custom specific range 1MHz or more? If it is not, would a 3D ...
0
votes
0answers
47 views

Form of the received signal in a MIMO communication

I am reading an article which is related to MIMO communication networks. Consider that there are \$U\$ users, each of them have \$J_{u}, u=1,...U\$, different layers. We want to calculate the received ...
0
votes
3answers
127 views

There is a missing component in this circuit and couldn't figure out why?

I'm designing a BA1404 Stereo FM transmitter and I found the following source: Source Link You can find the component list, circuit scheme and the other stuff on this page. But when I look at the ...
-2
votes
1answer
42 views

My Rf reciever circuit on battery ,but not with a rectified xformer output as source

I just made a Rf circuit that turns on and off a relay depending on the transmitter's message The circuit is working fine when i connect it to a 9v battery. But i cant get the circuit to work with ...
-1
votes
1answer
71 views

Will BA1404 circuit work with TEA5591A

For an electronics project I would like to build stereo FM transmitter and receiver circuits. I was just wondering if these two circuits would work together. The BA1404 circuit can be found here. ...
0
votes
2answers
311 views

2.4 GHz versus 434 MHz transceiver for home automation

I am working on a project that uses an Arduino Uno R3 and will have one receiver and one transmitter. I'm going to use this for home automation within my home in India. I want to know which ...
0
votes
0answers
153 views

WS-RX-02 Receiver Range in Arduino

I have been preparing the receiver using WS-RX-02 receiver and arduino Uno R3 board. My connections are as follows. 3 GND PINS on RECEIVE UNITS are Connected to GND of ARDUINO 2 VCC PINS on RECEIVER ...
0
votes
0answers
107 views

Useing RC Switch Library for Transmitter and receiver in arduino

I have a RF remote and want to replace this with Arduino using RC Switch library. I want to sniff the codes from existing remote and send using RC Switch library in arduino. Is there any tool ...
0
votes
2answers
115 views

Best way to wirelessly transmit and receive data

I'm working on a project that requires wireless transmission and reception of data. I wonder what the best technology would be. It is not tons of data maybe not even a kilobyte. And the range should ...
0
votes
1answer
407 views

FM Radio transmitter and receiver circuits

I'm planning on building a FM transmitter and receiver circuit for an electronics project. I was just wondering if these two circuits would work together. Also would they be suitable for transmitting ...
1
vote
1answer
107 views

Connecting dipole antenna for transmission

I have a small FM transmitter on a breakout, the antenna is a single connection. It came with a thin blue wire for this purpose; below it spirals up and out the top of the photo. This works fine ...
0
votes
1answer
800 views

Generating Rolling Code with Arduino for RF Switch

I am working home automation using Arduino and TX/RX module. From various sources I learned that Rolling Code based RF Switches are having better security. I have following queries How suitable it ...
0
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0answers
194 views

RF Receiver sniff encryption

I am trying to build a home automation system using Arduino Uno R3 and transmitter and receiver module. I will be buying a RF remote switch. RF remote switch specification says it uses pairing coding ...
1
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1answer
110 views

Help with a RF reciever circuit

Recently I have been working on a basic RF receiver, but my efforts so far have proved fruitless. I designed the following circuit based of of previous research into the topic. According to what I ...
2
votes
1answer
134 views

A question about resonance and crystal radio?

This is a circuit of crystal radio transmitter. I've tested it, and it works properly. but I can't understand everything in this circuit... L1 and C5 make resonance frequency, Would you tell me if ...