Hello all friends.
Does anyone have experience replacing SIK radio with ELRS AirPort?
Happy flying //YB
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Not yet, but I’ve ordered the new 915 MHz ELRS Tx and Rx from Radiomaster and plan to give it a try in the next month. I fly my planes with the 2.4 GHz ELRS now, so the 915MHz should give good radio separation.
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It is much nicer. Better range and higher speed. (2.4ghz)
I managed over 7km instead of a few hundred meters with EU-SIK at highest data rate.
I plan to switch to ELRS
Is ELRS Airport full mavlink ? I mean how many data drop
it is a transparent serial port like SIK radios. → standard mavlink.
Just following up on trying ELRS Airport on 915MHz while using 2,4 GHz ELRS for the RC link. It works, but I have been disappointed in the lag time between the attitude and sensors of the plane and how it is displayed on Mission Planner. I’ve mad a number of tweaks to MP parameters and Telemetry rates, but I still get a 2-3 sec lag time, so I’m very disappointed so far. If I can’t resolve this, I’ll be trying Bluetooth between my transmitter and my PC.
Did this ever improve for you?
I’m on the fence about purchasing another SiK radio pair vs. Radiomaster bandit micro + Bandit BR3 diversity Rx. The price for the SiK radio is $103.50 vs. $103.87 for the bandits. I’m willing to pay $0.37 more if it works better. But it seems like it’s worse(?). I think there’ve been some firmware updates this year. Has it gotten better in the last 9 months?
you can use the mLRS firmware to do the same thing if your hardware is supported.
MAVLink over ELRS is pretty much fully supported right now, there are minor changes that will arrive with Ardupilot 4.6 (new dedicated MAVLink message for RX inputs to FC, some fixes for MAVFtp). The only real issue is that Yaapu’s Telemetry Script isn’t supported.
IMHO external ELRS modules are better suited for use with MAVLink thanks to the built-in USB port.
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Thank you for the replies.
I have to be honest: I’m still not clear on the difference between ELRS Airport and mLRS. Do the same rules apply, such as: AirPort - ExpressLRS
Frequency band
If you plan to use two side-by-side ELRS links on the craft (one for RC and one for telemetry), it is HIGHLY recommended to use different frequencies for each link. For example, you will see good results with RC on 2.4GHz and AirPort on 900MHz. The range will be severely reduced if both RC and AirPort are on the same frequency band.
And also, is it fast? I’ve read anecdotes of people saying there’s a 2 second delay between rotating the vehicle and the mission planner artificial horizon displaying it. I don’t get lag with SiK radios.
mlrs has about 3x the bandwidth. Basically ELRS uses a lot of very small packets, thats how they can do the really fast RC update rates but it means that mavlink packets have to get split into a lot of packets to get sent slowing it down and adding latency, mLRS uses a lower number of larger packets, so you get more bandwidth at the expense of update rate and a little less range but unless your racing or freestyle 30hz or 150hz RC makes no difference, the 10-15% reduction in max range is due to it needing to receive more data to make up a packet. It also has mavlinkX, basically mavlink compression that gets you more bandwidth than you actually have.
mlrs doesn’t support as much hardware as ELRS so you would need to look at what’s supported, most ELRS receivers work. the ESP32 TX modules are still a work in progress, stm32 modules work.
Thank you for the information. The Radiomaster bandit I was looking at seems like a bad choice at the moment; it has an ESP32 module. Instead, the Mateksys mR900-30-TX looks like a better choice. That’s the ground station solved.
Rx question; which is better: Full diversity @ 100mW, or zero diversity @ 1000mW? I can’t decide between the Mateksys mR900-30 and the Bandit BR3 ExpressLRS 915MHz Receiver.
1000mw is going to go much further than diversity.
the mR900-30-TX are not compatible with the ELRS receivers, they use more modern RF modules so you will need to use a pair of the MR900-30 modules, they get about 30% faster data rates than the older modules ELRS use that run at 19hz on mLRS that’s essentially the same chip from the frsky r9 modules.
yapuu telemetry is also supported.
https://www.mateksys.com/?portfolio=mr900-30-tx
https://www.mateksys.com/?portfolio=mr900-30
Thank you for the insight. mLRS all the way it is!
I just bought these two modules and I cannot get it to configure to what I wanted.
for example, Firmware tx-matek-mr900-30-g431kb-default, USB = COM/CLI, connect USB directly to computer, install STM VCP driver, select STM32 COM port
I believe the default firmware installed are:
RX Receiver: rx-matek-mr900-30-g431kb
TX module mode: tx-matek-mr900-30-g431kb-default
I know ultimately I need to override it with TX SiKtelem mode: tx-matek-mr900-30-g431kb-siktelem. Right now, I just want to understand the hardware connection’s health and usage. Currently, both are blinking green when both are powered ON.
Does anyone have the experience to share?
the default firmware should be indeed installed
so that the CLI/com is on teh USB as you tried
if you are on Windows: one should not need to imstall a driver (I don’t understand why everyone always srtarts with installing drivers LOL)
as regards your issue:
- ensure you are using teh right COM port, you may have multiple
- you need to send a command in the CLI to get a response
- you say both blink green but in the picture the tx doesn’t. It may just be the time of the photo been taken, but wanted to mention
it is somewhat better to go to the mlrs discord channel, you’ll get much better help there than here (it’s just an accident I have seen your post)
driver, are you referring to the DFU Driver? The Mateksys mentioned it.
as for the Install STM32 VCP Drivers (COM mode), it was mentioned here, “Make sure DFU driver has been installed. Check out “Install DFU Drivers” in this page”.
Stupid me.
You saved my day. thank you.
I followed the steps and got this error, do you know why? The binary file was downloaded from here.
17:21:38 : STM32CubeProgrammer API v2.18.0 | Windows-64Bits
17:22:44 : UR connection mode is defined with the HWrst reset mode
17:22:45 : USB speed : Full Speed (12MBit/s)
17:22:45 : Manuf. ID : STMicroelectronics
17:22:45 : Product ID : DFU in FS Mode
17:22:45 : SN : 207A30925532
17:22:45 : DFU protocol: 1.1
17:22:45 : Board : --
17:22:45 : Device ID : 0x0468
17:22:46 : UPLOADING OPTION BYTES DATA ...
17:22:46 : Bank : 0x00
17:22:46 : Address : 0x1fff7800
17:22:46 : Size : 44 Bytes
17:22:46 : UPLOADING ...
17:22:46 : Size : 1024 Bytes
17:22:46 : Address : 0x8000000
17:22:46 : Read progress:
17:22:46 : Data read successfully
17:22:46 : Time elapsed during the read operation is: 00:00:00.008
17:25:17 : Flash sector erase ...
17:25:19 : Flash page/sector erase command correctly executed.Note: if flash sector is protected, it will not be erased.
17:25:41 : Opening and parsing file: tx-matek-mr900-30-g431kb-siktelem-v1.3.04.hex
17:25:41 : Memory Programming ...
17:25:41 : File : tx-matek-mr900-30-g431kb-siktelem-v1.3.04.hex
17:25:41 : Error: Parsing fail
17:25:41 : Error: In line 2752 :
17:25:41 : Error: parsing count, expecting hex digit, found 'v'
17:25:41 : RUNNING Program ...
17:25:41 : Address: : 0x00000000
17:25:42 : Error: Start operation failed
I also had problems with the STM32 Cube Programmer. Then I tried the mLRS Web Flasher https://mlrs.xyz/flash/ and it worked straight away.
The operation is self-explanatory. However, it only runs under Chrome-based browsers.
thank you. I think my problem is with the way I download the hex file.
For Web Flasher, do you have to enter into any mode? DFU in FS mode? I tried Web Flasher in DFU in FS Mode, and the error was downloading.
I got this connection lost, and I am not sure if it is considered healthy flashing.
It seems successful. !! Rx param version smaller than Tx param version. !!
[Tx][17:30:47.283] v;
[Rx][17:30:47.327] v>
[Rx][17:30:47.327] !! Rx param version smaller than Tx param version. !!
[Rx][17:30:47.327] !! Please upgrade receiver. !!
[Rx][17:30:47.327] Tx: Matek mR900-30, v1.3.04
[Rx][17:30:47.327] Rx: Matek mR900-30, v1.3.01
[Rx][17:30:47.327] >
[Rx][17:30:47.327] empty cmd
[Rx][17:30:47.327] >
[Rx][17:30:47.327] empty cmd
Does anyone know how to use p name API? p Mode works, I am confused.
[Edit]
Okay, got it p tx_power;
[Tx][17:43:44.585] p Tx Power;
[Rx][17:43:44.608] p Tx Power>
[Rx][17:43:44.608] err: invalid parameter name
[Rx][17:43:44.608] >
[Rx][17:43:44.608] empty cmd
[Rx][17:43:44.608] >
[Rx][17:43:44.608] empty cmd
[Tx][17:41:51.543] p Mode
[Rx][17:41:51.578] p Mode>
[Rx][17:41:51.578] ConfigId:0
[Rx][17:41:51.578] Mode = 31 Hz [1]
[Rx][17:41:51.578] 1 = 31 Hz
[Rx][17:41:51.578] 2 = 19 Hz
[Rx][17:41:51.578] 4 = FSK
[Rx][17:41:51.578] >