Here is a preview of my long range wireless modem.
It's based on a Radiocrafts 868Mhz module (RC1180HP) with 450mW RF output power and good receiver sensitivity.
I'm going to use this for modem telemetry and antenna tracking, one in groundstation and one in the airframe
It has the following features:
1x LCD 102x46dots
4x Buttons
1x MicroSD slot
3x analog to digital inputs
1x I2C
1x SPI (if LCD is not used)
1x RS232 (TTL)
2x Timer outputs (used to connect a 4017 to drive servos)
4.5 to 32volt DC input
Dimensions are 44mm x 55mm x 5mm
More info will be added later.....and yes it will be open-source, I will share all design info if you want....
Edit:
Here you can find the schematics: RC1180HP-Modem.pdf
Comments
Interesting project as it helps me in getting on the RF side of FPV, something that interests me a lot. Would be a great help if the schematics and board files are made available. Would be interested in two boards plus any indication where to get the components that are not available from any electronics store. Maybe a kit of parts if that is possible.
@Ahmad, thanks!
@Johann, range is highly depending on antenna system and regulations you want to meet, but more than 5Km LOS must be possible.
@abey, that's why I like this statement of the Radiocarft datasheet :"The use of RF frequencies, maximum allowed RF power and duty-cycles are limited by national
regulations. The RC1180HP-RC232 is complying with the applicable directives within the
European Union when used within these limitations."
The legal discussion is always a interesting part, using the radiocrafts module it's upto the user, but it's certified so it could meet the regulations which is good, the +27dBm is the maximum RFoutput but is configurable by the user.
Even a +10dbm output with 100% duty and a high gain yagi antenna is not legal because regulations are about ERP ;-)
Before I used a Wi232 module at +15dBm (32mw) and got a solid link with 9600baud at 4Km LOS, but this was with a 12 element yagi at the ground station pointed to the plane.
If there is interest in this project I can upload the schematics and board files, I think the board layout will be ready next week so I will place the order for about 10 boards next week, if more are needed let me know. I think the price for one board is around €10,- but depending on the quantity.
I hope there is some interest for this project because code has to be done from scratch, so help is very welcome !
Peter
Peter