Questions tagged [transmitter]
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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Can a radio transmitter somehow detect the number of receivers in its area?
During conversation, a colleague proposed that over-the-air television and radio broadcasters can determine the number of viewers or listeners based on the "load" on their signal. This seems to me ...
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Optical audio transmitter can't handle speech
This is a question relating to my project on an optical audio transmitter.
I wired up a very simple device in which I use an audio signal transformer (EI14) to modulate the intensity of a laser beam (...
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Can I break a radio tranceiving device by operating it with no antenna connected?
People tell me I shall not use my CB-radio station without an antenna connected or it will result in damage of the device. Is this true and why is this?
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Why are color difference signals transmitted rather than R,G,B signals?
In color television systems back in the early days, people used to transmit color difference signals (Y-R) and (Y-B) along with Y, which is the luminance signal. My question is why are color ...
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Best practice in transmitting sensor analog signal over longer distances (approx. 100') -- in cost sensitive products for microcontrollers
I'm looking for best practices for transmitting an analog sensor signal over long distances to a microcontroller such as the Arduino running at 3.3v or 5v. Keeping costs low is imperative.
SPI and ...
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Schematics for a simple radio transmitter that can be built only with passive components?
Fantasized in some of the survivalist, post-catastrophic novels, movies or docudramas is the radio built only with handcrafted or scraped components.
Beyond the popular appeal of this stories, I ...
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What is this circuit diagram found on an FM transmitter?
This is the circuit diagram on the transmitter at a local FM radio station I clean at (I'm a janitor,) but I'm also studying electrical engineering. I'm puzzled by the circuit diagram on the ...
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How do two UARTS know which baud rate to use?
I am reading about the standard protocol for UART and I think that if the receiving UART does not have any idea on what baud rate the data was transmitted, there would be lots of problems. If the ...
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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 ...
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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 it ...
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ultra low power mini wireless transmitter / receiver?
I'm looking for suggestions for a wireless transmitter & receiver combination. I'm basically just trying to bridge several buttons over a wireless signal(s) (i.e. send a 1 bit signal) in as small ...
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How to end sending data over I2C by Slave or Master?
Let us say a Slave or Master is sending multiple bytes to the receiver on I2C bus and the number of bytes is not defined before hand. So then how will the sender tell the receiver that it has no more ...
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What is the advantage of differential Manchester
I can see the advantage of Manchester code over NRZ: you get clock and data in one signal combined. But what does differential Manchester add to that?
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Will a spark gap transmit a signal an FM receiver can "hear?"
Forgive me if this question is a duplicate, I looked around but did not see anything that quite fit.
The scenario: I found a box of old FM receivers, the kinds used (I think) for assistive listening ...
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What's the purpose of the band-pass filter in an RF transmitter?
What is the purpose of the marked band-pass filter?
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Measuring direction of object (or angle of signal origin)
I am interested in somehow tracking the "compass" direction of a moving object from a reference-station -- in other words, something similar to submarine sonar systems (although I'm unsure how those ...
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How does someone design a low frequency FM radio transmitter?
I'm relatively new to the topic but I'm intending to transmit some data from a measurement system in a cave to a receiver on the surface. I understand that I can use a SDR (software defined radio) to ...
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Any wireless technology to find the distance between transmitter and receiver
I have a static transmitter and a mobile receiver. Is there any wireless technology to find the distance between the two in real time.
Apart from using gps!
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Tube transmitter tuning
I am trying to tune/tweak/repair this transmitter for a friend of mine. It is oscillating, and it has rf power on the antenna, but it just doesn't seem as "strong" as it should be.
The diagram says ...
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Are my power calculations on this MOSFET Power Amplifier accurate?
Thanks to the help of electronics.SE, I've designed my first power amplifier, intended for transmitting CW on 7 MHz.
Before I order parts and build it, I'd request a design review.
One important note:...
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Digital Compass identifying direction of travel for use with trains
I work in a control center for a train company in the UK. Our trains work in either direction but only one end has first class carriages. Because trains on our network reverse quite a lot it is ...
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modem free high base AM data transfer possible?
not a very experienced EE, but I was thinking about a system for high speed data transfer,
and it is fairly simple conceptually, so I imagine that there must be serious flaws with the method,
because ...
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Data over a 5V DC power connector
I am looking for a simple way to encode some data over a dc power line. (Probably using a very low cost IC) In my design, I have a port that provides 5V, 200mA for connecting some device, but now I ...
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Strange-looking FM transmitter circuit
I found this simple FM transmitter circuit:
I built it an it works rather nicely. There are many simple FM transmitter circuits on Google, most of which look basically like this:
These work by ...
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Does an RF receiver constantly consume power?
I'm building a battery operated robotic arm and would like to use a cheap, short distance RF transmitter/receiver kit to trigger it. However I would like to know whether the receiver will constantly ...
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FM Transmitter Modulation
I am designing an FM transmitter as a learning experience and for fun, but I am having some difficulty with FM modulation. I am using a VCO with a Colpitts topology and common emitter configuration. ...
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A complete Radio electronics guide
I want to learn all the basics about making a simple radio project.
The project is simple... One transmitting device (which only sends out analog signals of some decent frequency.. say 50MHz) and one ...
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Difference between ultrasonic transmitter sensor and ultrasonic receiver sensor?
What is the difference between ultrasonic transmitter sensor and ultrasonic receiver sensor?
Can an ultrasonic receiver sensor be used as an ultrasonic transmitter sensor or vice versa?
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Need suggestion in choosing an effective wireless Transmitter and Receiver
My requirement is to transmit a binary form of data from one Road Junction to another road junction which is around 4 to 5 km away.
I am going to get the traffic information from each road in the ...
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Microphonic SAW transmitter?
I built this very simple SAW transmitter, with a simple "spring" antenna for the right frequency. To test it, I tuned a portable receiver to around 433.92Mhz and fine tuned it until I heard silence. ...
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How to build cheap radio propagation beacon?
I want to build a Radio Propagation Beacon but I would like to find an integrated circuit that does most or all of the work of the transmitter.
Transmit to 28Mhz (Ham 10-meter band)
Allow me to feed ...
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FM transmitter design?
I stumbled across a relatively simple FM radio transmitter online.
Credit: makezine.com
I wanted to understand how it works (it is called "super simple" on the website), but several hours I have ...
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How small can a spark-gap transmitter be made?
How small can a spark-gap transmitter be made? Wikipedia's got plenty of pictures ranging from "desk-sized" to "room-sized", but those are mostly either early, inefficient ...
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How can I reproduce ambient EM fields inside a Faraday enclosure?
I am part of a research team looking at the possible effects of EM fields on psychological function. The experiment calls for participants to perform a series of tests while inside a Faraday tent that ...
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Can someone break down how this receiver works?
I'm having difficulty understand how this receiver works due to its size. It was taken from this site: http://jap.hu/electronic/rf.html. It is on top labled toy car receiver.
The toy car transmitter ...
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Can I use a DAC to tune a VCO?
I found some FM transmitter circuits with the MAX2606 VCO.
Example:
Can I replace R1 with the DAC output from an AVR microcontroller? Or can I connect the DAC directly to Pin 3 of the MAX2606?
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How does a cube sat communicate with ground station with a 1w antenna
I heard that cubesat signals can be received with a hand held radio. Its confusing me that how a 1 metre antenna radiating 1watt energy can simply be received using hand held radios. I am designing a ...
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Wireless transmission/reception through 100 feet (30m), including concrete wall
I have an electrical engineering degree, but little experience in building wireless equipment. I need to transmit a signal through about 100 feet of distance, including a concrete wall. I need ...
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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 ...
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How to find out what radio frequency is being emitted?
Let's say I have something akin to a garage door clicker. How can I discover the frequency and message it sends with no other information on the device? I want to decode this to the electrical ...
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FM Transmitter Circuit
I'm trying to make a FM transmitter work properly. I built the following circuit :
I can synchronize with 94.8Mhz channel on any FM radio, I know that because the original sound from that radio is ...
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can I use a choke 150uH inductor for my AM transmitter circuit?
I am trying to develop an AM transmitter but I am having problems with getting a variable capacitor and inductor (for the rf circuit) in my location. I was able to find a choke coil with an inductance ...
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Best communication option for multiple arduinos?
My father and I want to develop a cow pedometer to measure a cow's activity. The idea is that if you can measure a cow's activity you can detect when she enters heat. Detecting heat with sensors will ...
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How do I determine the proper FM transmitter strength?
I want to build an FM transmitter that will transmit (on an unused frequency) from my laptop (near my video projector) to my receiver (about 20' away on the other side of the room). Then, I thought ...
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How do I calculate the frequency of an FM transmitter circuit?
Below is an FM transmitter circuit I found on the web that I would like to build from scratch:
How I would calculate the carrier signal frequency so that I know where to tune my FM radio?
If I want ...
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How does this FM transmitter work?
I'm an electronics student and I have been trying to understand this FM transmitter diagram (taken from electronicshub.org) for a long time. I had put efforts to learn it by surfing the web but parts ...
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Why did my FM transmitter mysteriously die?
I made a little FM transmitter project a few months ago. I used an Arduino, a litle 4-digit serial LED display, a couple of buttons and an FM transmitter component with breakout board
I had this put ...
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Why do receivers have a choke but transmitters don't?
Here's a receiver I found on the web:
And here's a transmitter:
[
Why do receivers have an inductor specifically designated as a choke (RFC) in their circuits but transmitters don't?
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How can I modify the frequency of a simple 433MHz transmitter module?
How can I change the frequency of a simple RF transmitter?
These are the transmitters in question:
Background Research
On this question s3c says:
To change the ...
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Changing frequency on RF Link
I am using these RF link modules for a project since I need a cheap, small, and simple wireless link between two microcontrollers. The data being sent is a single integer and can be spam sent to ...
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