Update 4/2/2017 – New article for those of you interested in doing this set-up on non-Naze flight controllers.
If you’re a Spektrum fan like me, your best option for a receiver for your miniquad is a satellite receiver. You may be surprised to find out that each Spektrum satellite receiver contains all of the electronic components need to receive control signals from your transmitter and send these signals to your flight controller. Not only that, but they often actually outperform standard RX antennas in range. Finally, since they communicate with the flight controller using a Serial protocol, they have the lowest control latency that money can buy.
If you’re looking to learn how to set-up Spektrum on a flight controller other than the Naze, we have a great guide of for that too! This guide also covers how to bind your Spektrum satellite directly from the flight controller software.
DSM2 vs DSMX
There are two Spektrum protocols on the market: DSM2 and DSMX. DSM2 is the older technology that does not have true frequency hopping and thus suffers from interence problems which may affect range and your ability to fly at big events. Wherever possible, we recommend you use DSMX satellites.
Spektrum has some excellent marketing materials on both protocols on their website. You can check those out here.
There are a few options for purchasing DSMX satellites:
Standard DSMX Satellite:
The standard DSMX remote satellite, packaged with most Spektrum receivers. If you own a Spektrum radio, chances are you have a few of these laying around. The good news is if you don’t need them in your planes/helicopters, you can repurpose just a single one for your quad. Since these are co-packaged with so many other receivers, they can be found for almost half of the retail price on eBay or other second-hand marketplaces. I would recommend looking there. You can also buy them direct from Amazon here for $35, though I recommend you buy the race receiver described below.
DSMX Quad Race Receiver:
Spektrum has actually embraced the use of satellite receivers in race quad by coming out with a custom receiver they call the “DSMX Quad Race Receiver”. This receiver has dual built in diversity receivers, which increases range by reducing multipath interference. It has antennas with coaxial extensions, which make them easy to extend away from your quad’s carbon fiber body, which typically blocks radio signals. Finally, it has the autobind feature, which makes binding the RX to your transmitter as simple as powering both on in close proximity to each other. Perhaps best of all, they are pretty affordable even when purchased brand new: they are now generally found for $25-$30, comparable with any of the FrSky offerings. The one downside to this receiver is they lack the ability to provide RSSI like classic satellites and the LemonRX satellites. You can buy these from Amazon here.
- DSMX Quad Race Receiver with Telemetry:
This upcoming receiver is due to be released in October 2016. It is similar to the Quad Race Receiver, but it includes the ability to interface with Cleanflight-based flight controllers to provide telemetry down to your Transmitter. This means you can get voice warnings when your battery voltage or signal strength gets low if your TX is so equipped. It also has a smaller form factor, and weighs slightly less than the Quad Race Receiver. The downside is this receiver costs $50. You can buy this receiver here.
- Lemon RX satellites:
Lemon RX is a brand out of Singapore that makes receivers that can communicate with Spektrum transmitters. Notably, they offer a satellite receiver with coaxial extensions and diversity, just like the racing quad satellite above. Perhaps most importantly, they cost as little as $12. Up until Spektrum dropped the price on the race receiver, the LemonRX diversity satellite was our favorite pick of the lot. You can buy this satellite here – but beware, shipping times can be up to two weeks!
In this guide, I am installing a standard DSMX satellite on a Naze Rev6 flight controller. The installation procedure is identical for all the other types of satellite receivers. Some flight controllers on the market come with a Spektrum satellite connector built into the board. If you purchased one of these boards, skip to the “configuration” section below. Other flight controllers do not have a satellite connector or special slots to connect your satellite to. On these boards, you will need to do some further research on how to do the installation.
The first thing you will want to do is bind your satellite to your TX. There are several ways to do this, depending on what type of receiver you have. If you have the DSMX Quad Race Receiver or the DSMX Race Receiver with Telemetry, you should do this binding entirely in software after you are done building your quadcopter. If you are using an older Spektrum satellite or a LemonRX satellite, you’ll want to do the binding first using a spare Spektrum RX to be able to make use of RSSI.
Binding using a spare Spektrum RX
The classic way to complete the binding process is to:
- Get out an old Spektrum (or OrangeRX or LemonRX) receiver.
- Plug the satellite RX you will be using for your quadcopter into this receiver along with a bind plug
- Power up the RX.
- Bind your transmitter to the RX in the standard way.
This process binds both the RX and the satellite receiver, and now either can be used to receive commands from your transmitter.
Once this binding is complete, you can get rid of the “normal” RX. The satellite will now talk to your TX by itself. However, I would keep the master RX around to check the lines on your cable before putting it aside.
Binding using the flight controller
The other way to bind your RX is using the flight controller. Support for this feature was added recently to both Betaflight and Cleanflight. You’ll want to do this after you’ve finished building your quadcopter. We have an separate article that walks you through this process.
Now onto the actual installation of the receiver. You’ll need to sacrifice one of your Spektrum satellite cables in the installation process. Cut it so that the remaining wire is long enough to run from the FC to the location you wish to put your satellite on the quad. Make sure you can locate your satellite RX in a place on your quadcopter where the antennas will stick up in free air.
Now you’ll want to solder this cable directly to the flight controller board.
For the wire I used in the above picture, the grey wire is the signal (RX) wire, black is ground, and orange is power (3.3V). Do NOT plug the satellite into a 5V source, you will burn it out. My experience has been that 5V serial is OK (even though some people say that this will destroy the RX), but a constant 5V power source will surely destroy it.
I would recommend you check which wire is ground and which wire is 3.3v with a volt meter before hooking anything up. You can do this by plugging the satellite cable into the main RX and probing the voltage coming out of the wires. Once you’ve found the 3.3v line, solder it to the Naze32 input closest to the screw hole. Ground goes adjacent to that, and signal goes into the pin furthest from the screw hole.
Once you’ve finished soldering the wires on to the FC, I recommend adding some hot glue or something similar to insulate the wires and reinforce them so that they cannot be pulled out easily in a crash.
Working with connectors
On some receivers, notably the Spektrum Race Receiver with Telemetry, you may need to manipulate the JST-ZH connectors that plug into the receiver. This is because this receiver has a telemetry wire that is not used by Betaflight quadcopters. Check out our quadcopter connector guide for some tips and tricks on how to work with plastic connectors like these.
A Cleaner Installation
There is an alternative way to installing the satellite wiring to your Naze for those clean freaks out there. The board was specifically designed to accept a solder-mounted JST-ZH plug. These can be purchased here. By soldering on a plug like this, you dont have to butcher any wires – just plug your satellite right in. There’s still nothing wrong with soldering your wiring directly to the board as is documented above – this is just another option.
Next up, you’ll move to setting up the Spektrum Satellite in Betaflight Configurator. This process is outlined, along with the rest of the quad setup procedure in our expansive software setup guide – we recommend you check that out. If you want the cliffs notes for just the Spektrum satellite installation, though, read on.
The satellite will be powered by USB power once plugged in so, to configure your receiver, you can just plug the bare Flight Controller in without connecting the main battery. Also power up your TX for testing purposes.
First, open up the “Ports” page. Change the appropriate UART row to “Serial RX” and disable all of the other options. On the Naze, this will always be “UART2”. On F3 flight controllers, this will generally be UART3. Press “Save and Reboot” before continuing.
Next, go to the “Configuration” tab and scroll part of the way down. In “Receiver Mode”, select RX_SERIAL. In “Serial Receiver Provider”, select SPEKTRUM2048. For DSM2 receivers, you should SPEKTRUM1024 here, but all DSMX receivers are SPEKTRUM2048. Click “Save and Reboot” again.
Finally, go to the “Receiver” tab. If you have your transmitter on, you should notice that your stick movements should now change the values in this window. However, you’ll need to select TAER1234 from the “Channel Map” drop down box to get the channels lined up properly. Now go through each channel (Roll, Pitch, Yaw, Throttle) and verify that they all move the corresponding bar inside of Cleanflight. Hit “Save” one more time, and go fly!