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Retro Edition MkII

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Linar Yusupov edited this page Jun 20, 2026 · 17 revisions


Retro Edition Mark II is a successor of SoftRF Retro Edition.

The Mark II uses the same STMicroelectronics® MCU ( STM32F103 ) that older Retro Edition does. The STM32F103 microcontroller was very popular between 2010 and 2020. That's why we call the design as Retro.

The Retro MkII is based on third-party's hardware - Ebyte® E80-900MBL-02 product, which is available for direct purchase from manufacturer at more or less reasonable price (10+ USD).

Ebyte® E80-900MBL-02 uses he most recent and advanced Semtech LR2021 multi-band radio on the market



Compatibility 1

Type Protocol FLARM OGN tracker PilotAware Skytraxx SoftRF
Radio FLARM AIR V7

 

1090 ES
ADS-B

2
Data FLARM NMEA

  Garmin GDL90

 

Dump1090  

1 - it is necessary for a reader to distinguish the difference between statement "compatible" and statement "fully compatible".
     SoftRF implements only a reasonable minimum of the protocols specs. No "bells and whistles" so far.
2 - Reception of DF17 traffic 'downlink' frames only.

ADS-B Out remark

No doubts that an amateur-built non-certified low-cost ADS-B transponder is possible.
It was shown to public by our own "proof-of-concept" study for :

However, as a certified and instrument rated pilot with 20+ years of experience, in no way I will give a tool for every looser in the world, all he/she can afford is to spend 10 USD for the Ebyte® E80-900MBL-02, to abuse the ADS-B technology and compromise my own flight safety and flight safety of every other air law abiding pilot.

SoftRF firmware does intentionally exclude every possibilities to transmit anything on 1090 MHz radio frequency.
Any attempt to contribute the transmit feature into SoftRF from aside will be blocked at very early stage.


Comparison

Edition Retro ES Nano  Retro Mk.II 
Picture
First appearance 2019 2022 2025 2026
Manufacturer you Great
Scott
Gadgets		 RadioMaster
RC		 Ebyte
SoC STMicro
STM32F103		 NXP
LPC4320		 Espressif
ESP32-C3		 STMicro
STM32F103
sub-1GHz radio Semtech
SX1276		 Maxim
Integrated
MAX2837 and
MAX5864		 Semtech
LR1121  		Semtech
LR2021 
Protocols AIR V6
OGNTP
FANET
P3I		 ADS-B  AIR V7
OGNTP
FANET
P3I
ADS-L  		ADS-B 
AIR V7
Wi-Fi 2.4 GHz
802.11bgn
USB 2.0 device 2.0 device CH340
USB to UART

Summary

New Retro Edition Mark II

  • uses the same SoC as Retro Edition ;
  • it can receive ADS-B traffic @ 1090 MHz like ES Edition does ;
  • compact enough to operate together with a UAV autopilot. This makes it a good ( ADS-B receive ) companion device for Nano Edition

Disclaimer

SoftRF firmware for Retro Edition Mark II is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

In general a lot of Chinese DIY electronics manufacturers are known to behave this way:

  • sometimes they may not apply necessary Q.C. before releasing of a product from factory ;
  • they may arbitrary change schematics and electronic components from one batch to the next one.

Author of SoftRF firmware:

  • will reject any hardware related claims associated with Ebyte® E80-900MBL-02 product. Ask for support from seller or manufacturer ;
  • reserves the right to suspend or terminate support of Ebyte® E80-900MBL-02 in the firmware at any time.

For the time being ( June'26 ) there were no critical hardware issues reported for current version of the Ebyte E80 product. However things my change over the time...
If you have issues with bringing up your new Ebyte® E80-900MBL-02 or just not happy with the product - be prepared to execute your Purchase Protection plan.

Bill of materials

Required

Number Part Qty Picture Source
1 Ebyte® E80-900MBL-02 1 Ebyte Store
AliExpress

Important

Make sure that you are ordering -02 variant of Ebyte® E80-900MBL device.
Earlier made -01 variant uses previous Semtech LR1121 radio which is not able to receive ADS-B @ 1090 MHz. Driver for LR1121 radio is NOT included into SoftRF firmware for Retro Edition MkII.


Recommended

Number Part Qty Picture Source
2 Antenna
1090 MHz		 1 AliExpress
3 Test Stand PCB Clip 2.54mm Spacing 1 AliExpress
4A ST-LINK V2 adapter 1 AliExpress
4B DAPLink adapter 1 AliExpress

Quick start

TBD


Settings

Procedure of settings change is explained here.
Settings description is located there.

Important

EASA ADS-L radio protocol selection is not applicable with current version of SoftRF Tool app for Android - use Online Tool method instead.

If you are an application developer and you think about to add the Retro configuration menu into your software, please, use:

LEDs

  • steady red PWR LED indicates unit power on status ;
  • blue LED1 blinks when the Retro MkII transmits a radio packet ;
  • blue LED2 blinks when device receives a radio packet.

Enclosure

When a basic cover from moisture, grease and dust is sufficient for you - it is quite typical to use a heat shrink tube for this purpose. Matching diameter of the tube for Ebyte E80 board is 35-40 mm.

This is an example of Dongle Edition - Retro will have a quite similar look.


Hardware

SoftRF

SkyView

Flight Recorder

Adapters

Software

Firmware

Tools

Protocols

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