Wireless modules and simple setup, what is required?

[tasmod]

Hi all,

I have a friend who has asked me to design a radio link for simple on/off control at 868MHz.

Now I've never even looked at this before so I'm unsure as to a simple solution.

I've seen data transceivers on ebay, but what would be best, I assume a simple data stream would be adequate.

If anyone has any idea of a suitable pair of +10dbm modules please post the details. I'm somewhat confused by the choice, with some as rs232 others mentioning uart etc.

The idea is to send to a remote location a signal to turn on/off an output. That's it, nothing fancy.

In software I guess a unique ID then a code to select the action. I also considered as I was considering a transcever pair, a signal back to confirm output selected.

Rob

[tasmod]

OK I've found Dave Houstons excellent examples page, now i guess I just need pointing at a suitable pair of modules.

+10dbm is needed for a longer reliable range, the antennas are no problem.

I'm still confused by the choice of module, i suppose I'm saying i'm too dumb to understand the different protocols

Incidentally, the choice of 868MHz was his, apparently the place where this is to be used is full of 433 devices and he wanted to avoid a clash.

[tasmod]

Found this transceiver module on Farnell.

Anyone tell me if it's suitable for this use. I see it has SPI, I2C and UART listed as protocols.

Zulu RF 868MHz Module

[tasmod]

Hmm noticed that one has abuilt in processor.

How about this one
high-power-radio-transceiver/

3.3volt operation and logic levels ? Not sure on that one. Does a 16f628 at 3.3v working output at 3.3v logic levels. Sense says it should, although at bottom end of chips working voltage range.

Rob

[Chirpy]

if it's running at 3.3v, then yes, it'll output at 3.3 logic levels, and there's always the alternative of using something like a voltage divider with a 1.8k ohm and 3.3k ohm resistors if you need to convert the voltage from 5v to 3.3v.

[tasmod]

Thanks for that.

I've decided to go with the Ciseco hi power transceivers.

I've written some preliminary code based upon Dave Houstons code. I need to add prelim ID followed by string then acknowledgement just in case of power outage.

[Charlie]

OK I've found Dave Houstons excellent examples page, now i guess I just need pointing at a suitable pair of modules.

Can you post a link to the page you are talking about?

[mackrackit]

Mr. Houston's site
http://davehouston.net/

[mtripoli]

I just finished a project using Linx Technologies 900 MHz transceivers. Mouser has them: http://www.mouser.com/ProductDetail/...rSQqdnUWL1o%3d

Super simple to use - these are "air wires" meaning they don't force a fixed protocol on you; you can transmit/receive just about any kind of data you want (literally, serial, PWM, etc). This is a "big deal" if you don't want to get bogged down in the details of using a fixed protocol for your data.

As usual; the data sheet will be your best friend. They have demo systems available (I highly recommend buying the system to jumpstart your project - you can hook your uC to the board and be underway in minutes).

Good luck!

[Dick Ivers]

Hi mtripoli, What range distance are you aiming for with the Linx 900 mhz transceivers? Is your project one-way or two-way communication?