Radio Definition and 691 Threads

I've been trying this for 3 hours and I'm getting nowhere. These are the graphs I made for Hydrogen Intensity vs Frequency for a radio telescope that transits the sun and galactic arms of the galaxy. http://img220.imageshack.us/img220/5904/helpgraphia6.jpg...

Not sure if I'm in the right forum, but does anyone know anything about the mechanism behind using radio waves to disassociate hydrogen and oxygen atoms from salt water?

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...

how can you build a device that can produce radio waves?

While driving home from Portland today I listened to the only station that was actively reporting on today's election results. It took awhile to realize that this was right-wing radio because for a time the reporting was just news. But then she - the show's host - started in on her naive...

There are hundreds, if not thousands, of RF signals all around us from those at VLF frequencies to microwave frequencies and I suspect if you set up a very long random length of wire as an antenna, there would be a resulting induced electrical signal that is the sum (and differences) of all...

I have a simple question - but I somehow doubt there is a simple answer. 1) I would like to start a small, non-commercial, home transmitted FM Radio Station - mostly for fun and as a hobby. I have seen an 18W transmitter for a reasonable price. I live on relatively flat land in the country...

Let's say that you make a huge (radius of a few meters) coil of wire. Will radio waves cause a current to run through it? If so then how much? 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?

Hello everybody. As I'm new here, maybe someone can help or direct me to other resources that will assist in my investigation. I am looking for information that can help me select the proper radio frequency for use in a new project. The following is an overview of the project and the...

while dealing with radio telescopes how can we remove the noise and other disturbances like microwave radiation etc.

The objective is to "design and construct an FM radio receiver" that is able to tune to commercial FM radio broadcast channels spanning from "87.5 MHz to 108 MHz", and to produce audible demodulated output. can anybody help me with a simple circuit for this assignment with proper values for...

Have these papers been discused. http://arxiv.org/abs/0704.1125 High Galactic Latitude Interstellar Neutral Hydrogen Structure and Associated (WMAP) High Frequency Continuum Emission Authors: Gerrit L. Verschuur (Submitted on 9 Apr 2007 (v1), last revised 23 Jul 2007 (this version, v2))...

Hello, Is there a formula to convert a certain radio frequency to temperature? Thanks.

Homework Statement Designing an FM Radio Receiver. You enjoy listening to KONG-FM, which broadcasts at 96.6 MHz. You detest listening to KRUD-FM which broadcasts at 96.5 MHz. You live the same distance from both stations and both transmitters are equally powerful, so both radio signals produce...

Hi all, I'm now very busy trying to findout how to block external RF at my apartment room. I'm on 23rd floor. A huge radio boardcasting tower (714KHz, 90MHz) is just 20 meters away running along with my building. It's higher than 25 floors. I know that many GROUNDED conductive surface can...

Homework Statement An AM radio station broadcasts with a power of 21.0 kW at a frequency of 910 kHz. Estimate the intensity of the radio wave at a point 18.0 km from the broadcast antenna. Homework Equations I= p/A I1/I2=r2^2/r1^2 w=2pi f The Attempt at a Solution From the...

I've been puzzling how it is that you can tune into a signal on a particular frequency. How can it be possible to get rid of all the other signals that are added together? I don't know how much of this makes any sense, but I have tried to specify the problem mathematically. Suppose R_1(t)...

[SOLVED] Find an FM Radio station's wavelength, frequency given Homework Statement An FM radio station broadcasts at a frequency of 101.3 MHz. What is the wavelength?Homework Equations Vsound = 343m/s @ 20 deg C λ = v/fThe Attempt at a Solution I used the formula λ = v/f and got something...

Hello good members and guests of PhysicsForums. Whats the deal with this? Are we going to be fueling vehicles with sea water now? http://green.yahoo.com/index.php?q=node/1570

Hey guys. I know conspiracy theories and the discussion of 9/11 in general is frowned upon on this forum, but I am looking for some experts in structural engineering, aeronautics, physics etc. for my 9/11 educational radio show tomorrow morning. I use a website called BlogTalkRadio to do my show...

I am looking at a cheap $100 shortwave radio, the Kaito KA-2100 (google it, there are a bunch of links, too many to mention), and I would like to know if disabling the AGC (automatic gain control), is possible for use as a radio telescope. Now I don't know that much about radio and electronics...

If net neutrality isn't enforced, and businesses are allowed to manipulate the pipes of the internet possibly allowing only a small number of websites who can afford the fee faster transmission, do you predict that The Internet will just be another version of cable or satelitte tv , where , just...

Seems like a pretty basic question.. Most will say Marconi... But is that really correct ? Aquafire

first HI to everyone! I have a question: is there a (simple) way to reduce radio wave speed at it's source - transmitor (e.g. to 100 or 1000x less then the speed of light)? thx in advance

Homework Statement AM radio allows a speration of 10kHz between frequencies of different radio stations. Why do AM radio receivers need a large Q? Estimate the Q required for good AM reception. The Attempt at a Solution I'm really not sure where to begin! :confused:

Since the last thread got locked, how about legal means to get free electricity? One example is an AM crystal radio that receives it's power via a simple antenna. The power source is a radio stations broadcast. As posted previously, there are numerous devices like windmills or water...

supposedly u are stuck on an island battery died on your radio u have: 10 m of wire (copper?) and stuff found naturally on the island and u need to run a radio at 3 volts what would u do?:bugeye:

heres a simple question I somehow couldn't find an answer on the internet. we know radio waves only reflect (significantly) when it strikes an object with size greater than the wavelength, but I'm not sure what exactly defines the "size" of the object. For example, if I were to confine a...

Discussion: And there is very little Liberal talk radio?

hey i m kinda new at making radio controls... just made a simple RC with a 2 bit Tx- Rx kit that i got from a local shop... all my robots are wired... so i want to move on to a proper radio control(coz they don't teach RC makin in mechanical engineering:cry: :cry: ) ... can anyone suggest me...

Hello, Can you please tell where radio waves originate from? Thanks, Glynis

The tutorial on how to make a search form with multiple search options was excellent! http://www.mediacollege.com/internet/javascript/form/multi-search.html However, is it possible to use radio buttons instead of a drop-down list?Can someone be kind enough to show me the code for it...

Homework Statement Why can't you make radio transmitter that transmits visible light instead in the same way we transmith AM signals? Homework Equations The Attempt at a Solution Im thinking maybe they would not be very effective as their wavelenth is so small, they would die...

Homework Statement Compare this to the power received on the ground from a geostationary satellite with a 1 W transmitter and with a transmission footprint of 1000 square km across (assume uniform power in footprint). The Attempt at a Solution I don't know where to start on this one...

I'm not using the template here because it doesn't really suit this sort of question. Anyway, I'm writing about the Medicina Radio Observatory and I'm trying to find a site that will give me a history of the observatory. The history page provided by the IRA, which is listed as the 'official'...

hi all... Something doesn't quite add up here: A radio wave is an electromagentic wave, right. It therefore travels at the speed of light, right. Then why does it actually take a finite amount time (like secoonds or even miliseconds) to travel a couple of kilometers...

It seems that Earth is constantly being bombarded by radio waves that have been created by natural occurrences. Concerning the search for intelligent life, what sort of filter is used to disseminate between a naturally occurring radio wave and a radio wave created by intelligent life.

Are the length of radio waves relative to the scale and gravitational force of origin? In other words, if one increases, the scale of the Earth and total solar system by 10 times when this planet emits human produced radio waves, will the wavelength also be 10 times larger?

How does a Radio Antenna Work? I'm trying to get a grasp of the physical mech. You generate an AC signal on a conductor (i.e. at 30mhz) The free electrons on the skin of the conductor osc. back/forth at 30mhz. The acceleration / decleration of the free electrons causes photons to be...

Hello! I'm reading into the LHC and the "bunch structure", and I'm confused in general, and I think knowing what the radio frequency acceleration scheme is might help?! As in, how does it work? And does it actually use radio waves? Any help would be greatly appreciated! Thanks, Samantha

Hey i was wondering if someone can help me out with radios and whatnot...i know making transmitters are illegal but i was just curious as to how they work as well as receivers. The thing that confuses me is how do you get information to and from the signal? I mean if i made a tank circuit that...

For long wavelengths like radio is dense material better to block, or shield, as it is for short wavelengths like x-rays? You can block out the photons of the visible part of them electro-magnetic spectrum by pulling the curtains closed, so how come radio waves like your AM radio, cell...

I have a project in one of my classes, the aim of the project is to interface a circuit which you will design with a computer through a USB port, I read a lot about software defined radio's and I was thinking of building a very basic one which will receive AM signals and then convert them...

http://www.cbc.ca/quirks/media/2006-2007/mp3/qq-2006-09-23e.mp3"

Hey guys i was just doing a bit of poking around and i found this site. I was wondering if you lot could help me. You see i have to compare and contrast two types of similar communication. i chose AM/FM radio transmitions I know some of the bare basics like: They transmit by minipulating the...

this may be kind of dumb question but... How do XM and Sirius broadcast so many stations? Isn't evey broadcaster given one frequency.

If 10,000,000 radios are all tuned into a small local radio station, wouldn't the radio station crash, or what would happen?

I was wondering, how come with Satellite TV, I have to have a dish pointed directly at the satellite while with Satellite Radio, I can just have an antenna pointed anywhere in the sky? Is it because satellite radio is at a lower frequency or do they just push out more power?

Hi to all of you i am James i am researching about campus fm radio can anyone help me to to my research because i ask this moment i already gathered some information but i don't know how to start and can anyone give me some reference about this. thank you very much in advance.