RF Communication between 2 BS2's

Aidanx1

Hello. I was just wondering how I would go about transmitting data between 2 BS2's using this transmitter and reciever?



This is the data dor the transmitter:

Operating Voltage: dc 3-12V
Current: 5-45 mA
Modulation: AM
Frequency: standard=315
Range: 1000m

Pins: VDD, TXD, GND, ANT.


This is the data for the reciever:

Operating Voltage: dc 3-8V
Modulation: AM
Frequancy: 100 - 500. Standard=315/433
Sensitivity: -103 dbm
Transfer rate 4.8K pbs
Output: TTL

Pins: VDD, RXD, GND, ANT.

Any and all advice will be greatly appreciated. Thanks

Post Edited (Aidanx1) : 11/5/2008 12:56:56 AM GMT

Mike Green

You might be able to use the sample code for Parallax's transmitter/receiver pair. These appear functionally pretty much the same.

Note that your modules are rated only up to 4800 Baud while the sample code assumes 9600 Baud.· You'll need to change the Baud constants in the SERIN and SEROUT statements.· There's a table in the PBasic Manual that gives the Baud constants for various Bauds (in the chapters on SERIN and SEROUT).· Consult that.


Post Edited (Mike Green) : 11/5/2008 1:10:01 AM GMT

Carl Hayes

How would you do that? Unlawfully, most likely. Under what part of FCC regulations does this transmitter operate? Part 15, perhaps, which, however, requires certification and labeling by the manufacturer. Unfortunately, people make and sell radio equipment that cannot lawfully be made, sold, or offered for sale, and FCC hasn't enough enforcement personnel. But when they get caught, it hurts -- Pilot Travel Centers (truck-stop chain) paid some very hefty fines last year for selling illegal transmitters. This thing looks made-to-order for causing harmful interference to licensed services over a very wide frequency band. Using AM with square-wave modulation guarantees an extremely wideband signal.

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· -- Carl, nn5i

Aidanx1

Thanks Mike, I'll check it out. But on a more basic level I just need to know the general principles of opperation. i.e what data do I have to input, and at what rate? and how ill that data correspond with what that transmitter outputs?

Carl, I'm in the UK so the FCC doesn't effect me. However there are probably some similar laws in the UK but it's only a low power transmitter with a 1000m range (probably less). I don't think it will interfere with much, especially since it is only 315Mhz.

Leon

It's definitely illegal to use those modules in the UK and you could get into serious trouble if someone notifies OFCOM about your intentions. You could check with them to make sure:

www.ofcom.org.uk/


Leon

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Amateur radio callsign: G1HSM
Suzuki SV1000S motorcycle

SRLM

1000 m is pretty far... How many people live in that radius of your house?

Aidanx1

emm...500 maybe. I live in an urban area. Ok, to be honest I see the point you are all making. I have no desire to spam anyones radio signal. Theoretically then, what type of signal do I have to input, to get it to transmit and recieve? Do I have to input waves or pulses or what? and what should I expect to read from the output? I won't transmit anything until I check the legallity etc.

Leon

You need something that meets the various standards, like a 2.4 GHz module using the Nordic RF nRF24L01 or TI CC2500 chips. They only give about 50m range, though.

Leon

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Amateur radio callsign: G1HSM
Suzuki SV1000S motorcycle

SRLM

What about some of the sparkfun chips? Those get up to 1000m and are about the same size.