This company specializes in m2m (machine to machine) communication.
Also, http://twilio.com can send and receive SMS messages from web apps.
This company specializes in m2m (machine to machine) communication.
Also, http://twilio.com can send and receive SMS messages from web apps.
Two sources for HF to VHF upconverters for SDR experiments.
At Reddit /r/RTLSDR
http://www.reddit.com/r/RTLSDR/comments/12ebes/informal_upconverter_comparison_janielectronics/
Extends flight range to 1.5 – 2.5 kilometers
By Albert at Dronehacks
http://dronehacks.com/2011/08/21/ar-drone-rc-mod-extends-flight-range-to-1-5-2-5-kilometers/
Lego meets Arduino
audio transformer + crystal oscillator + battery = AM radio
At scitoys.com
http://scitoys.com/scitoys/scitoys/radio/am_transmitter.html
source of radio parts for this type of project:
http://www.scitoyscatalog.com/category/R.html
Radio Shack has audio transformers…
http://www.radioshack.com/product/index.jsp?productId=2103254
update 6/2014: audio version of the AM transmitter: https://reactivemusic.net/?p=12263
original post
http://dangerousprototypes.com/2011/10/05/am-sofware-radio-using-arduino/
Forum thread which gives a sketch to generate Morse code at 1337khz, with no additional hardware.
http://arduino.cc/forum/index.php/topic,8456.0.html
Tried this sketch and it actually works – local version is:
morse_code_AM_1337_xmtr
Here is a link to a circuit using a crystal oscillator component and a serial port from windows computer to turn it on and off to make cw, also a suggestion (below) to expand it to use audio modulation…
http://www.instructables.com/id/Build-a-computer-controlled-radio-transmitter/?ALLSTEPS
To those wanting to send audio (as in music/voice): You will need an audio transformer. The transformer has 5 leads: 3 on left, 2 on right. The 3 lead side: connect the audio jacks ground on bottom, input on top leaving the middle lead free. The right side: batteries + supply on bottom lead, the top lead connects to the oscillators input pin. What you used as the ground should be the same. Just plug it into the computers “audio out” plug. To transmit music, play it with whatever music player you like. Plug it into a mp3 player/ipod/cd player and take it with you where ever you go. To send voice, plug mic into pc “audio/mic/line in” plug.
More details on voice modulation…
http://www.instructables.com/id/Make-a-simple-AM-transmitter/
Yahoo Pipes
Alternatives…
http://stackoverflow.com/questions/2019887/alternatives-to-yahoo-pipes
Apatar
http://apatar.com/demo/Apatar_Overview/Apatar_Overview.html
Deri-Pipes
More to come