FM Radio Station Notes Part 24

FM RADIO STATION NOTES PART 24

TUTORIAL: How Radio Waves are Produced
http://www.youtube.com/watch?v=aAcDM2ypBfE#t=186

FM TRANSMITTER
As a reference to going even smaller and more simple, this schematic shows possibly the most simple one transistor FM radio voice transmitter design, using a common 2N2222 transistor and only three capacitors and two resistors. There's only 7 electronic parts total to this assembly plus batteries and the antenna. A power on/off SPST switch should be added to the schematic.

Parts List
R1 Resistor 4.7K
R2 Resistor 220 ohms
C1 Capacitor .01uf
C2 Capacitor 33pf
C3 Capacitor 6.8pf
L1 Coil
Electret Microphone
2 - 1.5 Volt Battery

A slightly modified version is at this web site:
http://www.sentex.ca/~mec1995/circ/fmt2.htm
http://www.sentex.net/~mec1995/circ/circuits.htm

FM RECEIVER
The video also includes a schematic diagram for a very simple matching two stage FM radio receiver. This battery driven radio has only two transistors, amounting to 6 electronic parts plus batteries, switch and antenna.

Parts List
R1 Resistor 12K
C1 Capacitor 220n
T1, T2 Transistor BF199
C Variable Capacitor
3 Volt Battery
SPST Switch
Earphones
Antenna

BF199 transistor data sheet
http://pdf1.alldatasheet.com/datasheet-pdf/view/2947/MOTOROLA/BF199.html

MOST SIMPLE FM TRANSMITTER
The simple FM transmitter circuit shown above is a spinoff of this project. It uses only one resistor, one capacitor, one transistor and one coil. The article is found all over the web. It has no microphone but the coil is so microphonic that it will pick up noises in the room via vibrations on a table. The circuit does not have any section that actively tunes the frequency. The transistor turns on via the 47k resistor and this puts a pulse through the 15 turn winding. The magnetic flux from this winding passes through the 6 turn winding and into the base of the transistor via the 22n capacitor. This pulse is amplified by the transistor and the circuit is kept active. The frequency is determined by the 6 turn coil. By moving the turns together, the frequency will decrease.  The circuit transmits at 90MHz which is at the low end of the 88 to 108 MHz FM band. It has a very poor range and consumes 16mA.

http://www.circuitlab.org/2013/02/schematics-easy-build-rf-transmitter.html

http://skema-elektronik.blogspot.tw/2011_02_01_archive.html

http://circuit-diagram.hqew.net/Simplest-RF-Transmitter-circuit-diagram_4095.html

http://www.talkingelectronics.com/projects/Spy%20Circuits/SpyCircuits-1.html

This Google search link will find a lot more simple FM radio transmitter schematics and projects.

SIMPLEST FM TRANSMITTER
Here's another link to a project claiming also to be the simplest FM transmitter ever made.
http://circuitsdiy.com/the-simplest-f-m-transmitter-ever-made/

This circuit has audio input and needs only 2 resistors and 3 capacitors plus a coil and transistor.

"For input from low power output devices, such as mobile, computer’s sound card, the value of the unlabeled capacitor is 0.1 or 104. For higher wattage outputs, the value is 0.01 or 103. An optional microphone pre-amp can be also added in this circuit to enable it transmit voice directly."

ANTENNA
One idea to create the small transmitter antenna is to use a small wheel bicycle used spoke from a children's bike available from a bike shop probably for free.

How to Change a Dark Detector into an FM Transmitter
http://www.buildcircuit.com/fm-transmitter-and-dark-sensor/

A dark sensor can be converted to a simple FM transmitter using a similar schematic layout.

The dark sensor will light the LED as the output indicator. The transmitter substituted a microphone for the LDR.

FM TRANSMITTER
This FM transmitter is very sensitive and it has transmitting range of 30 meters with a 9-volt battery. Reducing battery power will reduce transmitter range.

Comments given at the link about the transmitter
The circuit may work but it relies on a “Q-factor” from the coil and capacitor in the tank circuit to produce a high voltage.

This high voltage gives the circuit a good range. Firstly the coil and capacitor should be near each other. The coil should not have long leads. and a 22n capacitor should be across the supply to give the circuit better performance. The value of C2 is too high. It should be 10p. The coil should be 5 turns. The electret mic should not be connected directly to the base of the transistor.

FM Radio Station Part 4 Broadcasting

THE VOICE OF SCIENCE NOW BROADCASTING... Connected to a 9-volt battery, this is the first power on of the radio station. We're on the air, with an antenna so tiny, it's merely broadcasting to the other side of the table. This is the first successful test of the FM radio station with "across room range." There's always excitement when a "just built" project is switched on for the first time. It's always hoped that it works perfect the first time. Building projects is like a crap shoot - there's any number of things that can go wrong as Murphy's law dictates. In the case of projects, components often have a 10% failure rate and can cause some frustration in troubleshooting newly assembled projects. One can take a gamble and assemble the parts untested, or test each part for greater workability insurance. With this project, the radio station worked perfect the first time!

FM RADIO STATION transmitter broadcasting part 4
We're broadcasting into space! Who is listening?

This is the fourth installment about building your own radio station. On Monday December 23, two days before Christmas, at 10:00 pm, the radio station was turned on for the first time. A nearby FM radio was scanned across several transmitter harmonics, then settled onto the strongest signal. It's a success! "Testing, testing, 1, 2, 3..." came in loud and clear on the small portable radio tuned to the FM band.

The transmitter's coil was slightly adjusted to push the signal farther up the FM band to avoid several very strong radio stations around 98 to 100 MHz. The perfect test place was quiet at 101 and 102 MHz.

For initial testing, a tiny loop antenna is used which extends only about 3-inches high in the long direction when elliptical and is about 1.5-inches diameter when circular, perfect for across-room broadcasting.

The sensitivity is capable of overloading acoustical feedback and distance of the audible source to the mic is also sensitive. The orientation of the transmitter greatly effects reception and keeping it in one place is required. Hands near certain areas of the transmitter effect frequency and harmonics, although the portable FM receiver is ultra sensitive - a 10 band FM/MW/SW World Receiver model 6110 by Panda made in China. Its FM band ranges from 76 to 108 MHz with manual tuning and running from 3-volts. This radio was used for reception of objects in space such as the planet Jupiter and the Earth's Sun during the Lab's SETI program searching for extraterrestrial intelligence.

Radio Telescope Receiver
http://humanoidolabs.blogspot.tw/2013/07/radio-telescope-receiver.html

Don't Eat Us Safety Program Radio Telescope
http://humanoidolabs.blogspot.tw/2013/07/dont-eat-us-safety-program-radio.html

Radio Telescope Adds Spaceweather Radio
http://humanoidolabs.blogspot.tw/2013/07/radio-telescope-adds-spaceweather-radio.html

Radio Telescope Observatory Lab 58
http://humanoidolabs.blogspot.tw/2013/07/radio-telescope-observatory-lab-57.html

The FM band in this region of the country, serving up to 24 million people, contains strong stations in almost every position on the band from 76 to 108 MHz. Smaller stations serve a six million locality. Therefore the density of stations is unprecedented. Many of these stations may be underground as the government is working to license and annex these broadcast stations.

A weak station, or even one that has associated harmonics, will be lost in the signal hash, thus limiting the range.

The unexpected high quality of the FM transmitter is very good when trimmed and tuned. Voice is very audible close to the microphone. Backgrounds sound muted as desired although this requires more sensitive testing.

The high quality of such a simple circuit is attributed to the high quality of the parts used, i.e. the special am/fm, rf, amp, mix, conv, osc and IF ability of the 2SC1675 transistor, and the 1-watt output amplifier of radios in class B push-pull operations ability of the 2SC9013 transistor.

FM Radio Station Part 5 Index
http://humanoidolabs.blogspot.tw/2013/12/fm-radio-station-part-5-index.html

Radio Telescope Radar Tracking

 PART 4 - Tracking Radar Objects in Space
RADIO TELESCOPE RADAR TRACKING
This blog describes more add on capability for the radio telescope which we recently put into operation. This uses the same equipment to track objects in space which reflect radar waves.

The radar transmitter puts out waves that originate from Earth as man-made transmitters owned by the Air Force and NASA, used to track the positions of space objects. The FM radio band will work as a receiver, more specifically try the VHF-UHF tuning bands. The radio's monopole antenna is acceptable and try repositioning it for best reception. The antenna with receiver works well on an alt-azimuth mount with a flex wire to feed the audio to the computer processors sound card for signal processing.

This link offers more information.
http://www.neatinformation.com/science/space%20radar.html

Radio Telescope Receiver

10-Band Radio Telescope Receiver

RADIO TELESCOPE RECEIVER

PART 3 - The newly formed Radio Telescope Observatory Laboratory is working with two receivers for intercepting radio signals from stars, planets, and a Tiny SETI program designed to detect other civilizations across our galaxy. First we will examine a $10 ten band radio purchased and made in China. This is a Panda model 6110 that runs of two AA batteries. Eight bands center on the shortwave spectrum while one band is FM at 76 to 108 MHz and MW covers 525 to 1610 KHz. The radio covers a total of shortwave bands ranging from 5.85 to 21.95 MHz.

THE PLAN
The plan is to get the system up and running by solar and Jupiter observations and then fine tune the results for deep space and Tiny SETI Potential programs include the Sun, Jupiter, Aurora, Lightning, Meteors and SETI deep space. There is also a sub program to design and create a 5-inch refractor telescope on the antenna as an optical calibrating and spotting finder telescope. 

FREQUENCY CONVERTER
Useful free online frequency converters, convert MHz and KHz to meters, m.
http://www.translatorscafe.com/cafe/units-converter/frequency-wavelength/

http://www.onlineconversion.com/frequency_wavelength.htm


FM radio receivers typically receive signals in the frequency range 85 to 108 MHz (wavelength 3.5 m to 2.78 m)

 TOTAL RADIO COVERAGE
076 - 108.0 MHz
525 - 21.95 KHz
5.85 - 21.95 MHz 

POTENTIAL RADIO OBJECTS
Sun
Jupiter
Lightning
Meteors
Aurora
SETI

LIST OF RADIO BANDS
SW1  05.85 - 06.30  49 Meter
SW2  07.00 - 07.35  41 m
SW3  09.50 - 10.10  31 m
SW4  11.50 - 12.00  25 m
SW5  13.40 - 14.10  21 m
SW6  15.00 - 15.60  19 m
SW7  17.40 - 18.25  16 m
SW8  21.25 - 21.85  13 m

FREQUENCY DETAILS
10.0 - 25.0 MHz  Jupiter range (21 MHz ideal)
5KHz - 300 GHz   Radio waves penetrate Earth's atmosphere
Below 18 MHz     Ionosphere reflects radio back into space
3 - 40 MHZ       Decametric radiation
18 - 28 MHz      Sun & Jupiter detectable
18 MHz           Lightning & manmade sources
21 MHZ           Best band for listening to Sun & Jupiter
Above 24 MHz     Jupiter intensity drops 

DOING RADIO TUNEUP
Not all shortwave radio tuning faceplates are accurate. Find your place on the dial with WWV time signals. The 20 MHz signal may be the most useful. "24 hours a day and 365 days a year the WWV and WWVH radio stations provide you with time signals, solar activity information and geophysical alert broadcasts transmitted on shortwave at 2.5, 5, 10, 15 and 20 MHz. These stations are operated by the National Institute of Standards and Technology Time and Frequency Division , Boulder, Colorado. Details including hourly broadcast schedules can be found here . Note: unlike most time signal stations of the world which use the Single Side Band (SSB) mode for their transmissions WWV and WWVH use ordinary Amplitude Modulation (AM)." http://www.starkenburg-sternwarte.de/radio/links.htm

GETTING STARTED
First we need to examine only the radio waves that can penetrate the Earth's atmosphere. This is in the range of around 5KHz to over 300 GHz and equals wavelengths from a few millimeters to nearly 100 meters. The Earth's ionosphere will reflect radio waves back into space at a frequency below 18 MHz and thus these signals are not detected at the Earth's surface.

DECAMETRIC
Decametric radiation is in the range of 3 to 40 MHz, which equals wavelengths of 10 to 100m. Decametric means tens of meters.

JUPITER AND SUN FREQUENCIES
Jupiter and the Sun may be detected anywhere from 18 to 28 MHz. Tune to the unused portions of the shortwave bands.


LIGHTNING The point at 18 MHz, lightning is heard along with strong interference from manmade radio sources, and this reduces the chance of detecting extraterrestrial sources.


JUPITER DETECTION For Jupiter, the probabilities of detection drop sharply at frequencies higher than 24 MHz, because of the drop in intensity of the emission. So somewhere around 21 Mhz is commonly thought to be the best band for listening as it is well above the ionospheric cut-off frequency and generally free of man-made interference. 

SIGNAL RECORDING
THE SIGNAL from the receiver can be recorded on a computer, digital recorder, cassette recorder, or iPhone. This project uses apps from iPhone 4 and iPhone 5.

LINKS
Radio Telescope Receiver Part 3

Don't Eat Us Safety Program - Radio Telescope Part 2
Radio Telescope Observatory Lab 57 Part 1
Talking to Aliens
http://stefangeens.com/2005/03/talking-to-aliens-part-i-prelude/
Detecting Jupiter's Radio Emissions
http://www.spaceacademy.net.au/spacelab/projects/jovrad/jovrad.htm
Solar Radio Telescope
http://www.sunguntelescope.com/SOLAR_RADIO_TELESCOPE.html
Basic Jupiter & Solar Radio Telescope
http://www.britastro.org/radio/projects/BasicJupiter.pdf
NASA Radio Jove Project
http://radiojove.gsfc.nasa.gov/help/
Simple Radio Telescope
http://crystal.xxn.org.uk/wiki/lib/exe/fetch.php?media=brazil:radio_telescope_howto.pdf
Basics of Radio Astronomy
http://www2.jpl.nasa.gov/radioastronomy/
The Jovian Decametric Radio Emission
http://radiojove.gsfc.nasa.gov/library/sci_briefs/decametric.htm
Sample Helix Antenna
http://www.iceinspace.com.au/forum/attachment.php?attachmentid=16861&d=1158146700
Receivers for Jupiter
http://www.radiosky.com/juprcvr.html
THE ANTENNA - JOVIAN BASKETBALL HOOP
http://lasp.colorado.edu/education/outerplanets/lessons/grades6-8/The%20Jovian%20Basketball%20Hoop.pdf
Listening for Meteors
http://www.astronomyforum.net/comets-minor-planets-forum/104711-listening-meteors.html
"In reading about the Leonid meteors shower, which I believe is supposed to peak today, I picked up tidbits that I never knew. For example, using a FM radio (regular broadcast rcvr), you might hear quick, short burst of a distant station punching through with presence of meteors. The recommendation I read suggested tuning somewhere at the low end of the dial, where you are not hearing a station. Since FM radio does not follow the curve of the earth, FM stations have limited range. However, the ionized trail of a meteor will provide a brief medium for these radio waves to bounce off of. I think the term is called "pinging". Anyway, the result can be a very brief blast of faraway station popping through."

What shortwave frequency for "listening" to Jupiter?
"Try frequencies above 20 Mhz (the first detection of the decameter
Jovian radio bursts was something like 21.1 Mhz or so). Most seem to
like the range of 20 to 24 Mhz, although I have heard of some
observations as high as 35 Mhz. The emissions sound a little like ocean
waves on a beach. They can be surprisingly loud, but even so, it takes
a good shortwave receiver and a directional antenna (and a bit of luck)
to hear them." http://www.astronomyforum.net/amateur-astronomy-forum/36812-what-shortwave-frequency-listening-jupiter.html

Jupiter Observations of Shortwave
http://www.eracnet.org/observations/jupiter.htm
"One of the simplest things to get started with is to monitor Jupiter on the short wave band between 18 and 28 MHz which may be done as a School project or as an Individual. To do this go please to radiojove.gsfc.nasa.gov and download the hand books for the Radiojove receiver as well as the Radiojove Antenna. This will give you the basis to do a really good project. The antenna you may build using local components like TV Coax and wire. The splitter is a simple T piece with no electronics or phase switches in it. Simply bung everything together at best with a soldering iron and it will work ok. The Radio Jove Receiver may be purchased and is great fun to build up. I have built one and it is designed for beginners to build. If you do not want to build it you may use a short wave receiver tuned to a clear frequency near 21 MHz in AM Mode wide band..."

Listening to Jupiter Radio Storms
http://www.reeve.com/Documents/RadioScience/Jupiter Complete.pdf
From RadioUser - the new shortwave magazine, Sept. 2009

http://files.seds.org/pub/astro/SL9/jupradio/io_jup.radio "It appears that all one needs is a shortwave radio, 66" of stiff wire, 23" x 23" metal sheet (wire mess or aluminum foil), coaxial cable, wooden supports, screws and bolts. One can hear the Io/Jupiter interaction as well and meteors with this system. Robert Sickels says that Jupiter storms may be detected in un-used portions of the shortwave bands at anywhere from 18 to 28 MHz. When present at 18 MHz, say, they will not be found at higher frequencies. He says that Jupiter storms can be detected using a long wire antenna and a shortwave receiver like the Radio Shack SW-60. He shows a simple schematic to take the speaker output for input to a tape recorder and strip chart recorder. He says that many owners of shortwave receivers have already heard these noises but dismissed them without really knowing their origin..."

FAQ
http://radiojove.gsfc.nasa.gov/help/faq1.htm "We study both Jupiter and solar radio emissions to better understand their magnetic fields and their plasma [charged particle] environment. Studying other planets always helps us better understand the Earth, and this is true when we study Jupiter's radio emission. Earth also emits radio waves by similar processes, so we can better understand this process by listening to Jupiter from both ground-based and space-based radio antennas..."

USING A SHORT WAVE RADIO
http://www.experts123.com/q/can-i-use-a-shortwave-radio-or-a-ham-transceiver-to-listen-to-jupiter-and-the-sun.html
"You must be able to turn off the automatic gain control circuit (AGC). Many ham radio transceivers have an AGC mode switch (slow, medium and fast), as well as AGC off. In the AGC off position the receiver gain may be manually adjusted with the RF gain control. High gain settings may limit the dynamic range of the receiver causing it to clip the tops off strong bursts. The proper gain setting may take some experimentation. If your transceiver operates only in the ham bands then try either the 15 or 17 meter band for Jupiter. Solar bursts may be stronger in the 10 meter band where ionospheric attenuation is less. Of course you must use an antenna cut for the frequency of operation. A ham antenna such as a Yagi, or a quad can be used when Jupiter or the Sun is relatively close to the horizon. A general coverage shortwave receiver could operate with the JOVE antenna at 20.1 MHz. One of the few new general coverage shortwave receivers with an AGC off switch is the ICOM R- ..." more

RADIO STORMS ON JUPITER AUDIO
http://science1.nasa.gov/science-news/science-at-nasa/2004/20feb_radiostorms/

http://www.youtube.com/watch?v=e3fqE01YYWs

http://www.spaceweather.com/images2013/22jan13/ashcraft.mp3?PHPSESSID=tt1nvjpinsq537cee7f061sll2

Observing Jupiter by Radio
http://www.thrushobservatory.org/radio.htm "For casual observing, all that is necessary in the form of equipment is a shortwave receiver of good sensitivity capable of receiving in the 18 to 30 Mhz range. The 21 Mhz ham band is an excellent place to listen for Jupiter. Some older shortwave receivers fall off in sensitivity at about this frequency. In such a case, a pre selective amplifier may be included between the antenna and the receiver. These preamps are available commercially or may be constructed from plans available in amateur radio publications. The antenna need not be anything special; a simple dipole will do. In fact, directional antennas may be a hinderance if they cannot be tracked as Jupiter changes position in the sky. A somewhat better antenna system would include two dipoles, switchable from the operating position. one dipole would oriented north-south and the other east-west. Suspending the dipoles approximately 1/4 wave above a wire poultry netting ground plane may help in reception when Jupiter is near the zenith. If a directional antenna such as a 3 or 4 element yagi is used, then it may be helpful to tilt the antenna upward, perhaps 3O degrees or so, to achieve a compromise in reception when Jupiter lies at higher elevations. Lowering the antenna to a few feet above ground can also increase the angle of reception..."

RADIO ASTRONOMY
http://users.belgacom.net/astronomy/satellites_tv_radio.html
Did you know that you can receive radio signals from Jupiter with your shortwave receiver? Jupiter is a source of powerful bursts of natural radio waves that can produce exotic sounds when picked up on Earth using simple antennas and shortwave receivers.  The shortwave radio signals from Jupiter aren't a sign of extraterrestrial intelligence. The emissions are generated naturally by plasma instabilities in Jupiter's magnetosphere.  Most space physicists say that ionized gas in the upper atmosphere above Jupiter's magnetic poles sometimes behaves like a powerful radio laser or maser. The radiation can be so intense that Jupiter frequently outshines the Sun as a source of radio energy at ham radio wavelengths. Examples of shortwave reception of Jupiter's radiation:
http://radiojove.gsfc.nasa.gov/library/mm_exhibits.htm
http://www.spacetoday.org/SolSys/Jupiter/JupiterRadio.html

22 RADIO PROJECTS FOR THE EVIL GENIUS
MONITORING AURORA
 http://worldtracker.org/media/library/Physics/Evil%20Genius%20Books/22%20Radio%20and%20Receiver%20Projects%20for%20the%20Evil%20Genius.pdf

LISTENING TO JUPITER'S RADIO EMISSIONS
http://stargazerslounge.com/topic/170887-listening-to-jupiters-radio-emissions/ "Now that Jupiter is in our sky at night, it's a good time to listen to its radio emissions. This can be done with a shortwave receiver tuned to from 18 - 21 MHz during the night when this part of the spectrum is quiet (no ionospheric ducting of distant radio signals as is with the lower frequencies at night at this time of the year). What you are listening for is a background rush of noise that sounds like surf breaking on a distant shore. It will drift in and out slowly (several minuets) or quickly ( several seconds) from the background static noise level. The peak signal strength will be broad - about 1-2MHz wide - and can reach a signal strength of about "S-8" on a receiver's signal meter, with an outdoor antenna ( a horizontal dipole works nicely). Radios with built in antennas will pick up too much power line noise so the radio should have an outdoor antenna or be taken to a rural site (when you observe from a dark site) where power line noise is at a minimum. Any radio capable of receiving 18-22MHz will work and the mode that best hears the signals is SSB (single side band). Am will also detect it but not as well as SSB. And at other times of the year, when Jupiter is only visible during the day, the same signals can be heard as long as this part of the SW band is fairly quiet from broadcast signals, which they may be here during the summer months when this part of the band is "open". So as long as Jupiter is in the sky (day or night), you should be able to hear its radio emissions quite easily... just tune where you hear no broadcast stations or other man-made transmissions. The antenna does not have to be pointed at Jupiter at all. As long as the antenna (or radio) is outside a building where not much power line noise is evident, you should hear the signal. As long as Jupiter is within sight (even when cloudy), the signal should be heard especially at night when that part of the SW spectrum is usually dead..." 

JUPITER ON YOUR SHORTWAVE (GOOGLE BOOK)

RADIO SIGNALS FROM JUPITER (JOVE)
http://www.radio-astronomy.org/pdf/qex/radio-jove-proof.pdf

iPhone Data Analyzer
http://www.nastro.org.uk/how-to-build-a-radio-telescope.html
This output merely expands upon the last one to enable you to damage your iPhone as well as your laptop. I must confess, I have not tried this one yet, because I'm a little more concerned about damaging my iPhone, but I will try it at some point, when I have time, as I'm sure the risk is minimal. Having built Output 2, simply connect the audio cable to the 3.5mm audio output on your satellite finder, and use a 1/4” audio jack adapter to connect the other end to an iRig. The iRig is a component designed primarily to enable people to play the guitar through their chosen iGadget. There may be other connectors available that will enable you to feed the signal into the iPhone, so do feel free to look for something else if you wish, but the iRig is the most common one, which is why I mention it here. You can then download an appropriate app for the iPhone to analyse the incoming signal on your phone rather than your computer. Searching the App Store for 'sound analyzer' or 'oscilloscope' should bring up various results of use. Some of them are quite expensive (by iPhone App standards), but will be worth it if you wish to impress people with your new iPhone Radio Telescope attachment.

MAKE YOUR OWN RADIO IMAGE
http://www.nrao.edu/index.php/learn/activities/makeradioimage
 

Don't Eat Us Safety Program - Radio Telescope

Pioneer 10 & 11 Menu Map to find Earthlings

RADIO TELESCOPE SETI PROGRAM MOVES FORWARD

Arecibo Menu

The Big Brain initiative has moved forward by developing a more robust SETI, Search for Extraterrestrial Intelligence, radio telescope program. Speaking on behalf of the BIG Brain Initiative, Humanoido describes the "Don't Eat Us" Radio Telescope safety program, where, you contact us, we don't contact you.

As part of the The Asian Arena International Taiwan Radio Open Sky-faced Balcony Observatory Laboratory 57, this incognito search initiative employs a radio receiver that collects evidence in the search for intelligent life in the universe but does not transmit or give out our coordinates.

In the "You contact us, we don't contact you," radio telescope program, the radio telescope lab searches for bright radio emissions from populated planets around stars. A signature represents the combined radio signature of a planetary culture, such as their initial radio, TV, communications, and other electronic devices that contribute to the emission of a zone of RF. The populated culture won't have a clue that we're listening. In fact, these planets are often separated by vast distances and the passage of great time from the Earth. In perhaps many examples, the civilization will have evolved thousands, even millions of years into the future, from the date stamp signature of the signal we receive.

Listening to radio source emissions is more benign than transmitting our coordinates that could potentially make the Earth a fast food menu stop in space. In the early 70's, Arecibo, Pioneer 10, and Pioneer 11 contained menu maps directing alien civilizations to our doorstep (see illustration). Foolish or not? We know that science fiction, more often than not, is an accurate predictor of the future. How many science fiction movies exist similar to Alien, Predator, and even Star Trek with war-like Klingons are bent on destroying Earthlings or using humans as food sources? Listening to other civilizations does not alert those civilizations to our position.

LINKS
Radio Telescope Observatory Lab 57

High Speed Propeller Chips

Big Brain Focus - Propeller chip
HIGH SPEED PROPELLER CHIPS
The speed of the Parallax Propeller chip is already fast. By following the wondrous work of Master Beau Schwabe, the chip can be made amazing-blazing fast!

Beau has worked years carving out new elements for the Propeller chip, making possible transformations that the Big Brain is keen on adapting for supercomputer status.

One of these working miracles is the ability of chip to chip communication in excess of one million Bytes per second! A DIY Data Pipe can multiple this a hundred times!


BEAU SCHWABE OF PARALLAX: Here is a derivative of the high speed 8.42 Meg Baud (1.05 Million Bytes per second) Prop-to-Prop communication that I wrote some time ago. Last March there were several changes to the front end of both the Receiver and the Transmitter in the way that the handshaking took place. Before you had to make sure that the Receiver was up and running before you Transmitted... this is no longer the case, now it doesn't matter making it more user friendly. For just the average user, it's pretty straight forward... there is only one command to Send, and there is only one command to Receive. 

Basic Use:
To receive, just specify the pin you want to listen on and the address of where you want the received data to go to. Remember, this transmission is designed to send large packets of data, so if your just sending a few bytes here and there, this object is probably not for you.
RX(_Pin,_DataAddress)
To Transmit, is basically the same thing with a few more parameters... you specify the pin you want to yell on, the address of where the data is coming from, How much data you want to send in longs.
TX(_Pin,_DataSamples,_DataAddress,_00, 0)
Note: the last two fields are not used in the Basic setup, they will be discussed in Advanced Use. So that's it for basic use. 

Advanced Use:
The Receive is just the same as before, but it can be used as a function to return additional. information from the Server.
Command := RX(_Pin,_DataAddress)
This will receive data just as before and place it in the assigned address, but Command contains the size of the transmitted packet, a destination offset, and a Packet Command. Organized as such...
%ssssssssssssss_aaaaaaaaaaaaaa_cccc
where:
s = 14-Bit Packet Size
a = 14-Bit Destination Offset
c = 4 Bit Command
The Packet Size is obviously useful for determining how much data you received and allows support for variable width packets. The Destination Offset is unique in the sense that the Server has some control as to where the Data will end up on the receiver. Basically this value gets added to the DataAddress that you specify on the receiver so that the incoming data is written to a location starting at the DataAddress plus the Offset. This feature allows random block writes from the Server to the Client. The 4-Bit Command is just a way for the server to pass a specific command to the receiver. It can be used for anything you want. It's up to you.
For Transmission, it's just the same as the Basic Transmission as well, except the two parameters that were Zero'd out now have some meaning.
TX(_Pin,_DataSamples,_DataAddress,_DataCommand,_Of fset)

DataCommand as just mentioned is a 4-bit command you can pass directly to the Client and can be used for anything you want.
The Offset, also just mentioned, can be used to tell the receiver to write data to another location. This is useful when you only want to update a block or section of memory on the Client.
 
Finally, supplied Demo programs show a round-robin approach to sending data across multiple Propellers. The Idea is that you have one buffer that every Propeller sends around the loop ... "infinitely." To prevent collisions, ALL Propellers have access to reading the entire buffer, however, and this is what makes it work... Each Propeller can only write to a specific assigned location of that buffer. This isn't exactly true, but it's a good programming practice to implement. There aren't any collisions for similar reasons that you don't have collisions from COG to COG on a single Propeller. When a Propeller reads the Buffer, he is only allowed to write to the section that he is assigned to before sending the Buffer on to the next Propeller. (Note the Demo Code has this restriction lifted and can write to any location on the Buffer... But in my description, that's how you would typically manage the data across multiple Propellers and avoid collision. It works in the Demo, because there is only one Propeller writing to the buffer) In the Ring*, you can have as many Propellers as you want, with each Propeller only having a 3-wire interface... (Ground, TX, and RX) ... I have tested up to 5 Propellers with the supplied demo code. One Propeller must be identified as the Server to initiate the data ring, but all of the other Propellers are identified as Clients. Within each Propeller regardless of Server or Client ALL Propellers have equal access to the Data Buffer. I Hope this makes sense... Enjoy!!

Note: added a slightly newer version that addresses detection of the USB plugged into the PC. This prevents unwanted resets. Check this link out for a way to control switches across multiple Propellers, i.e. for lighting 
 

• High Speed Multi-Prop to Prop Communication.zip‎ (13.6 KB)
• High Speed Multi-Prop to Prop Communication_v2.zip‎ (14.7 KB)

Beau Schwabe | Parallax Semiconductor IC Layout Engineer Parallax Inc. * 599 Menlo Drive * Rocklin California 95765
www.parallaxsemiconductor.com
http://forums.parallax.com/showthread.php/134641-DEMO-High-Speed-Multi-Prop-to-Prop-Communication

*Note: in the case of the Big Brain, the Ring exceeds 100 chips with 800 cogs and enhancements for nearly a million processors.

14.5 Meg Baud Upgrade Ok, beta testers... I have run this DEMO and tested over 100 Billion data Bits with no Transmission Errors over the distance of 10 feet from one Propeller to another Propeller. Here is a beta release before I place it in the object exchange. ...· Enjoy!!
http://forums.parallax.com/showthread.php/99222-Propeller-DEMO-14.5-Meg-Baud-High-Speed-Prop-to-Prop-Serial-Communication