I would like to introduce you to a new radio modem that we developed for very long range datalinks!
Some of the key features of the RFD900 are as follows:
- Multi point and point to point link capability.
- Long range >40km depending on antennas and GCS setup.
- 2 x RP-SMA RF connectors, diversity switched.
- 1 Watt (+30dBm) transmit power.
- Transmit low pass filter.
- > 20dB Low noise amplifier.
- RX SAW filter.
- Passive front end band pass filter.
- Open source firmware / tools, field upgradeable, easy to configure.
- Small (30 x 57 x 13 mm), light weight (14.5g).
- Compatible with 3DR / Hope-RF radio modules.
- License free use in Australia, Canada, USA, NZ.
These modems are designed to support long range applications, while being easy to use and affordable.
These modems have been flying in various platforms and have demonstrated excellent performance in real applications.
RFD900 modems are now available at: http://store.rfdesign.com.au
Support within APM planner and the radio configurator from Michael Oborne is already available.
It works seamlessly with APM planner, all radio Mavlink parameters are available.
Update, December 2014: The RFD900+ with improved specifications is available now at:
Some one using RDF868x???
We are trying to install one of them, and we are having serious problems with GPS. This does not even do 3D fix.
It lost almost all satelites when we switch on the RFD868
We have tested RFD900 in the past and not problems but the I have a big problem RFD868.
someone with same problem has tested other frequencies or a filter?
900+ and 900X are not compatible. I do have multiple pairs of each.
The biggest advantage of the 900X is its fast processor which let ECC work without any lag.
Edward Sellars said:
I have one 900+ unit and one 900x. I cant get the 900x to talk to my 900+. I've tried all sorts of firwares, etc? Can anyone help or are they simply not compatible? The newest 2 900x firmwares say they will not work with older versions of the SIK firmware because of a change in frequency so i tried all of them and put 1.13 on my 900+. Any help would be great!
Thought I should update the thread on selecting between a primary and backup radio PPM stream.
I actually built the hardware to use the RFD900X's link status and another GPIO pin as switch inputs. However, link status is a 1 second square wave (so I needed a retriggerable one shot) and I ended up with 3 ICs. Plus, it didn't switch over if failsafe was caused by the transmitter on the ground or the cable to the ground radio.
So, I decided to go a different way. I used an Arduino Nano (and the Claymation PPM library) to inspect the PPM stream from the RFD900X. If the Nano doesn't detect PPM, detects failsafe on the throttle channel, or can't find a heartbeat (that I send from the transmitter) on channel 12, it directs a NOR gate to switch to an FRSky XSR receiver PPM stream.
This allows me to use the XSR (with 8 channels) directly from my FRSky transmitter. But, if I need more range (or want to also use channels 9-11), I can plug in my trainer cord from the GCS, throw a switch, and use the RFD900X PPM.
I still have a RC control path if either receiver fails and should retain a path even if the Nano fails (although it will be uncertain which radio the NOR gate will select in the absence of proper Nano behavior).
And the Nano + the NOR gate is smaller/weighs less than the 3 IC solution.
I have been using MP SiK 2.4 for some time now on a project with multiple sensor nodes on a mesh network. Now I would like to conserve battery power by having the sensors go to sleep and periodically wake up, sniff the network for packets and either respond or go back to sleep. The polling rate for sensors is 10Hz per sensor so the base node is sending polling frames at 10Hz x the number of sensors. I thought a sensible time to stay awake and sniff for activity would be two polling periods (200ms) and then sleep for several seconds which should drop the average current into the uA range but I'm finding that the sensors never detect network activity in that amount of time even though I know it is there because I have an extra node connected to a terminal program and I can see the polling frames coming from the base node. I looked through the datasheets for both the Si1000 and teh RFD900 but could not find a specification for time from power on reset till valid UART data. I think this would be a function of both the MP Sik firmware design and hardware synchronization on the RF side but I couldn't find any information on this anywhere. I tried detecting this time delay myself but it seems very random ranging from a few hundred milliseconds, to almost five seconds. Can anybody on this forum shed some light on this question for me?
I sent a friend request.
Please send me your email, and I'll send it to you.
Roger Ronald said:
This is excellent news. However.....
Where can I download 2.61? The web site (http://files.rfdesign.com.au/firmware/) has 2.55, 2.53, and 2.60 as point-to-point firmware downloads. No 2.61.
I'm running 2.60 and I get this from ATI5?:
RFD SiK 2.60 on RFD900xR1.1
This is available. Parameter GPO1_3STATLED will allow gpio1.3 to act as status led (ATS19, in latest version, check your version ATI5? to see where it is)
which shows when link is active. low when link is active. ie. pull a LED down to ground to show link is active,
or flashing as per LED on radio.
Feature is available from V2.61.
Roger Ronald said:
I would also like to make a request for a RFD900x peer-to-peer firmware change. An easy one. :-)
I'd like to be able to associate one of the GPIO pins with "link state" (high=link connected, low=link lost or vice versa).
I know this data is readily available. It's exactly the same information that's conveyed by the blinking or solid green LED, but it would be more usable if it:
The benefit of this option: The signal can be used to help select between a primary and backup radio PPM stream. If the RFD900x doesn't have a connected link, there's no reason not to use the backup radio's PPM stream. If the RFD900x does have a link, I'd logically AND that (externally) with a mirrored GPIO pin output signal to enable ground selection of the PPM stream via a toggle switch.
The GPIO pins alone are not sufficient for this function, since the GPIO outputs remain in their last state during link loss. Thus if you have the RFD900x PPM stream selected and lose the link (say the ground-station battery powering the RFD900x dies), you can't switch back to the other PPM stream.
I'd be more than willing to do the beta testing for this feature!
An update with some information I would have found useful. I won't state these as entirely definitive, but they may prove helpful to other folks: