Transmitter Definition and 122 Threads

Hi, i would like to make an android app and a gps transmitter. Where do i start? (Sorry if this is in the wrong section)

(Please go ahead and move this if it's in the wrong section.) I'm a science fiction writer doing research for my latest book and hoping someone can help. A technically competent character (far more competent than me with my long-ago high school physics) - let's call him Jake - needs to build...

How would I go about building a wave transmitter? Like in the noise cancelling headphones. I want to build a transmitter that absorbs sound waves, reflects them, and then shoots them out creating destructive interference.

Hi everyone I am an amateur modeler and am very interested in physics and am trying to to make a model car/roadway that can move and be controlled by a computer. I have managed to placing a motor in the models, but have not found battery's which are small enough and can run it. So what i...

I have read that you can make a very simple AM transmitter using only a crystal oscillator like the one described here: http://www.sciencebuddies.org/science-fair-projects/project_ideas/Elec_p024.shtml" I also read that you can make the equivalent of a crystal oscillator using a simple RLC...

I made a test for transmitter substances. Where the substances: Serotonin and Dopamine were compared. You probably heard about that you can do tests to see which one of the substances you've most of. And I got 86% on the Serotonin and only 14% of Dopamine. And I read about the different effects...

hello i have been given six weeks to design a low-power FM radio transmitter for my project however there are no lectures for this course so i have to do the research on my own. so far from researching on the web. i have found that a simple radio transmitter may consist of a number of stages...

Would this work? If I had a microcontroller output a 400mhz signal through one of its I/O then to a loop of wire. Would it transmit a RF signal at 400mhz?

I am thinking about launching a near space balloon. I'm going to send up a microcontroller with a pressure sensor that outputs audible beeps according to the height data from the pressure sensor. The problem is I don't have a way to transmit this audio data back down to earth. What is the...

Hey all! I have just constructed a RF circuit to try out. I made use of the T5-434-5V and the R5-434-5-128 transmitter and receiver pair and also the HT12E and HT12D as the encoder and decoder for the transmitter and receiver respectively. The schemetic I used can be found on page 6 of this...

What is the easiest, cheapest what to increase the range of this RF transmitter? Right now it outputs 8mW which gives it about a 500 foot range. I need it to be increased to about 40 miles line-of-sight. http://www.sparkfun.com/products/8946

---bluetooth transmitter------ hello every one I'm new on this site and this is the only forum i discovered so far that deals with electronics i need some help i'm trying to build a programmable bluetooth transmitter all i want from that transmitter is this i need to make a box (not a...

I'm making one of those simple FM transmitters. It uses a variable capacitor to tune. According to the writer of the tutorial, it is difficult to tune the circuit and RF is generally finicky. How would I use a microcontroller to tune the circuit? Thank you, -GiTS

I understand the basic principle behind pressure sensor calibration but i am still not able to do a calibration problem. Could someone Explain how you would go about calibrating a standard 4-20mA Differential Pressure Transmitter (DPT) to measure differential pressure in the range 5 to 20 psi...

Hi, How to check my transmitter signal power? I have found my transmitter in my friend shed and needs some new output transistors. But i don't know what is the power of my transmitter and if it worth to repair it. There is the RF board and also a encoder. There is also an amp so i don't know...

Hey guys, do any of you know of a transmitter/receiver device that can let you know the distance between them? I really need some help fast and would really appreciate it!

So basically i have this powerful electromagnet that generates an electromagnetic field that can levitate another magnet and withhold a load of 12oz and still levitate: My problem is, I want to be able to use electronics and send wireless signals through this strong magnetic field. I can...

Hi this is an instrumentation and control question A given tank has hot water process fluid in the bottom and steam as a gas on top. It has a differential pressure transmiter level with the bottom of the tank It has a wet leg on the low side of the d\p to control the steam condensate. If...

Homework Statement . I am just trying to understand this cicuit a little better. Especially the right half, I know that the left half is just acting as an amplifier but I'm not sure how the right half works. Also how is the frequency being modulated here? The attempt at a solution. I...

Homework Statement Introduction You are part of a team working on a software system for a mobile phone company. You have been asked to write a class capable of storing the details of a transmitter. The class will need fields to store the x,y coordinates of the transmitter and the...

i want to create my own radio transmitter and receivers and i don't want to use printed circuit boards or some kits .can any please provide details

Hi, I have a tiny (.6"x.6"x.125") 2.4ghz video transmitter that puts out about 1mw or rf power. I want to severely reduce the output power in order to reduce the range of this transmitter. instead of a few hundred feet line of sight range I would prefer no more than 10ft, and as little as 2...

I'm making a laser torch based audio transmitter n receiver using 2n5777 phototransistor as receiver what must be the min power of the torch

Hello folks. I want to buy a powerfull Fm Transmitter kit. Where can i find one at reasonable price? Cheers..

I am using the following receiver and transmitter for my project to form a ultrasonic communication system. I transmitted 5V Peak to peak voltage, 40 Khz frequency sinusoid from the transmitter and received the signal through the receiver. But the receiver shows the peak-to-peak voltage of about...

I am having to ask this from lack of electronic components in my area, so, I want to ask if it is possible to make an AM transmitter (short range) using a clock oscillator? I believe it might be possible, but as the crystal is 32768 Hz, it makes sense to ask, what kind of receiver set should I...

Hello all; Wifey got me a 20M QRP radio transmitter (1watt) for X-mas, knowing I love playing with this stuff:-p I have never heard of QRP before and was very surprised to find that there is no audio input on it:bugeye: So I stuck the kit together in about 2 hours and my spectrum...

Hi.I have got this circuit for a low cost short range FM transmitter but I am unable to understand the working and functionality of the circuit.Please help me in understanding the working.What I know is that its working as a VCO(voltage controlled oscillator) when input (through electret mic) is...

i want to ask what transmitter model can send the data over 1km?

hey guys I'm trying to build a 38khz transmitter that works about 5m(at least) but its unsuccessful.currently I'm using this circuit. but it can't use more than 50cm. i have no idea how to increase rage. equation is f=1/(0.8*R1*C1) I have some NE555 and a 9V battery some transistors and...

hello i was wandering can i use simple multivibrator circuit to generate 38khz signal to use as a IR transmitter for TSOP1738? i did some readings and calculations and came up with resistor and transistor values that gives 38khz. but since i don't have a oscilloscope i don't know whether...

(Update -- please read the third post -- I guess I'm wondering how an antenna works in particular).Hey, I can't seem to find much information on how the actually transmitting portion of a transmitter works -- how does one efficiently generate EM waves? Thanks!(I'm aware that the rough idea is...

I am trying to amplify extremely small signal(around 200 nanovolt) from a coil of wire on a ferrite to make a gaussmeter, I've seen some FM transmitter schematics online that I want to connect this signal to, Would a FM transmitter be able to work with a signal this low? I tried amplifying...

I want to know how to design fm transmitters. That is how to select appropriate values of the components. I need help

Homework Statement I need some points on how one would improve reception from a transmitter. The frequency of the transmission is originally 1GHz. The Attempt at a Solution Would deceasing the transmission frequency improve reception? Any other pointers?

This is not a HW question but an activity i am working on. The attachment is a symbolic AM transmitter. The carrier is 15MHz and message frequency is 2Mhz. I want to sketch the waveforms labelling them in as much detail as possible. Also sketch the output waveform in both time and...

I'm working on a personal project. Going to build a small AM transmitter. The goal is to be able to pick up the audio broadcast from my laptop, at various areas around the house with AM radios. I have purchased a crystal oscillator from ebay...

Homework Statement Seeking a method of calculating the number of photons instantaneously present within a given volume surrounding a radio transmitter at given power and frequency. Homework Equations E=hv, and other equations involving power and wavelength. The Attempt at a...

Hey guys I've done my transmitter. it works fine. But, I need to know how to feed it with input from a generator within taking into account that such a transmitter has two channels R+L. shall i use two different generators to feed every single channel ? I really need some help.

Homework Statement A radar transmitter used to measure the speed of pitched baseballs emits pulses of 2.0cm wavelength that are .25micros in duration. (a) what is the length of the wave packet produced? (b)to what frequency should the receiver be tuned? (c) What must be the minimum...

Hello everyone, I'm relatively new to dabbling with electronic circuits, so I decided to build my own FM transmitter using a circuit I found on the internet. The schematic has been attached as an image file. However, there are a few things I'd like to clarify. What exactly does the 'ground'...

Homework Statement A radio transmitter radiates at the power of 10 kW at a wavelength of 100 m. How many photons does it emit per second? Homework Equations E=hv, and some other equations of beginnings of wave mechanics. The Attempt at a Solution I had no idea where to start.Please do not...

I purchased a radio transmitter for my Zune, and it takes quite a bit of work to get it to function properly. I have not been taught much about how radio waves function or why my transmitter is behaving the way it is, so help me find a solution to my problem! When my radio transmitter...

Heyy guys do u know any data base or websites that provide any schematics or circuits of Wi Fi wireless transmitter.. Ur inputs are appreciated..

Pretty basic question, i think, it's either possible or it's not. Physics practical using an ultrasound generator and receiver components (in separate circuits, with the the generator rigged up to signal generator, and the receiver connected to an oscilloscope to take readings from). For the...

Hi all, i need some help on this circuit that I am building. i want to get the maximum current for my infrared emitting diode (Kingbright L-53F3C) datasheet->http://www.soselectronic.com/a_info/resource/pdf/king/L-53F3C.pdf" the peak forward current permitted is 1.2A (condition: 1/10...

[SOLVED] Spark transmitter 1. Hello, I am making this project ( a spark transmitter and a receiver), my problem are those coils below ( Lp, La, Lr). How are they connected to the circuit. three images are attached for the detail please help me thanks

How can I use radio wave to turn on/off a siren? I think it is possible for me to design a radio signal through this schematic: http://www.aaroncake.net/circuits/fmtrans.htm The problem is, how do I design a receiver that can switch on a siren by receiving the radio signal?

Hi, I am attempting to figure out how an FM transmitter I'm building works. I was wondering if anyone had some suggestions on a resource for transistor circuits or just has some ideas of how to go about figuring it out. If anyone is interested, here is the schematic...

Im working on a project and i would like know where i can find an ebook or site that could help me understand this technology. I will use an IR photodiode (Rx) and an IR emitter (Tx). the signal being sent will originate from a RS-232. So basically i have RS-232 <-> IR <-> RS-232, and so i...