Firmware update MMDVM clone

Hier is an article, how to update the firmware of a Chinese MMDVM clone, based on the original instructies by BD7MQB.

Here is the translated simplified way to update the firmware of the MMDVM clone, to OpenWRT Chaos Chalmers with a handy web interface.

You still have to make the basic settings via the LUCI web portal, which is standard with Open WRT. Here is a link with explanation:

We assume that you can set up a ssh connection by connecting your PC via WiFi to the open network that is generated by the board. In Windows you use putty and on the Mac terminal.

Log in withrootand password 12345678

Then you execute the following instructions from the prompt: (copy these lines without [Enter] and you will not make any mistakes)

cd / tmp   [Enter]

wget      [Enter]

mtd -r write ostar-18.06-ramips-mt76x8-widora_neo-16m-squashfs-sysupgrade.bin firmware       [Enter]

After the last instruction, the board has been updated.

With a 16 Mb memory version, a restart is automatically performed, with a 32 Mb version you have to take the power off and on again. Also possible with the 16Mb version.

The ip address after the firmware update is

The AP Wi-Fi is now called ON-OPENWRT, I thought, but I changed it myself later. This AP is up and running if there is no internet connection established.

The password for the Wi-Fi AP OSTAR-AP is Open1234

Log in now with user root and no password either through your webrowser ( or SSH to the same address. By the way, it is better to set the password with the instruction passwdand then enter your new password twice.

Finally if you are stuck again:

• Press and hold the WPS 3s to turn the Wi-Fi on or off.

• Hold down the WPS 10s to do a factory reset, where everything is as it was immediately after the update.




FT911A Transmit icon hangs

I solved the issue of the transmit icon staying in blinking mode and not due to hanging PTT or others </p


  • Switch OFF your FT991A.
  • Power and USB have to be physically disconnected. Pull the connectors.
  • Wait for 30 seconds
  • Re connect the PWR and USB and switch the FT991A to ON

That’s it !


Once upon a time somewhere in 2015 i bought a couple of these little converters RS232 tot TTL.


Here is how they work

From the RS232 Port – RX, TX and GND.  Thats the -> -<and the – signs.  Easy enough


-> RX

<- TX

On the TTL (Arduino)  side – DO NOT USE 5V use 3.3V as this toasts the device and heats up and like tops itself.  It certainly got very toasty when I put 5V across it.  This could be because I messed up somewhere in the wiring but it certainly works well for me.  I can also use the SoftwareSerial library as well so I don’t need to use TX/RX on the TTL Serial pins 0 and 1

So TTL is


-> – PIN X

<- PIN Y

For my device I used PIN 0 and PIN 1 – TX/RX – but I guess you can use other pins.

TTL RS232 Pinouts
TTL RS232 Pinouts




Hope this helps – it does work!


Gadgets schematics

Often i buy myself some small gadgets, only to forget about them .This plcae is my storage of these items and their technical descriptions etc

3Watt audio amplifier



Stepmotor driver : EASYDRIVER

EasyDriver v4.4


1pc NEW Aether X9C103S Digital Potentiometer Module F

Supply voltage: 3V-5V
Chip: X9C103S
PCB board size: 2.7 * 1.3CM
10K span potentiometer.
Colour is sent by Random
Potentiometer center tap between 0-10k slide in total 100 (potentiometer wiper typical impedance 40 ohms)
VL and VH digital potentiometer sliding rheostat port corresponding to the low-end and high-end, allowing the input voltage range -5V to + 5V.
Package Included:
X9C103S Digital Potentiometer Module

433MHz RF receiver module specificaties:

– Product Model MX-05V
– Werkt op: 5V
– Ontvangstfrequency: 433.92MHZ
– Ontvanger gevoeligheid:-105DB
– Maten: 30 * 14 * 7mm

433MHz RF transmitter module specificaties:

– Product Model: MX-FS-03V
– Werkt op: 3.5-5.5V
– Werkmodus: AM transfer rate: 4KB / S transmit power: 10mW
– Zendfrequency: 433M

433Mhz RF zender en ontvanger



Shengyang MH ET Live HB100 X 10.525 Ghz Magnetron Sensor 2 16M Doppler  Radar Menselijk Lichaam Inductie Schakelaar Module voor Ardunio - Aliexpress

AT-09 – Bluetooth

Arduino – AT 09 BLE module


OpenTracker+ | Argent Data Systems


OpenTracker+ | Argent Data Systems

Openwrt/Lede & APRX

Just before years end i have compiled the latest OpenWRT LEDE & APRX, and added OpenVPN and OpenSSL to it.  The files can be found in the download section. If you have another router, then drop me a line, or call me at DMR at 204 / 2044 or 2045.

Update OpenWrt-Lede with APRX.

On 26th of August 2018, i have uploaded new OpenWrt-Lede images with APRX 2.9.0

See the hamradio download area.

In case you need an image for a different router / platform, please drop me a mail.

Now Playing

Latest news from the site

Wie is online

3 bezoekers online
0 gasten, 3 bots, 0 leden