➔ Nextion TFT with Touch Screen
| 3 minute read
After getting the the MMDVM up and running for access to D-Star and DMR Brandmeister networks I experimented with the touch screen of the Nextion TFT display upon request of DL5BQ. The idea was to have a standalone unit that can for example be shut down with a single key press. Currently this is realized with a push button and a Python script (see [1]).
But as we added a Nextion display with touch screen to the Raspberry Pi running the MMDVMHost the idea was of course to use the touch screen for input.
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➔ Dissecting D-Star Streams between Reflectors
| 2 minute read
In preparation for some software development work contributing to XLX reflector software I wanted to disassemble the UDP stream exchanged between D-Star reflectors and a reflector and a connected node respectively. My wish is to add the output of the user configuralbe 20 character message to the dashboard. If running well I would also replace the link to aprs.fi with an output of GPS data transmitted by the client if available.
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➔ Resetting OpenPGP SmartCard
| 3 minute read
After my private key expired a few days ago I extended the lifetime of the key for another two years. Since I am using an OpenPGP SmartCard for storing the keys I had to edit card as well. After a few tries I gave up because gpg was always telling me that the keys exist on the card and was not willing to replace them.
Now I found a hint on how to reset the card to factory defaults [1] [2].
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➔ Customizing Tytera MD-380
| 3 minute read
A few days ago I received my Tytera MD-380 which I ordered in order to exeriment with the modified software and to have the chance to hear my own audio back. It was just a little less than an hour after it was flashed with the modified firmware allowing for talk group independent listening. I used the toolset by Travis KK4VCZ from [1] to compile respecitvely patch the original firmware for the radio.
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➔ Firmware Upgrade on DVmega without Programmer
| 4 minute read
A while ago I stumbled accross a thread in the MMDVM Yahoo group about the firmware upgrade on DVmega PCBs [1]. The interesting note was that Tom ON4TOP managed to upgrade the firmware without the need for a programming adapter. This is especially of interest for all those who have a dualband DVmega because the ATmega CPU in this case is a SMD one. For the single band radio there is an easier solution: Just pull out the ATmega 328P DIL processor and reprogram it with an Arduino Uno.
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➔ Latest OpenDV on Raspberry Pi
| 2 minute read
This time just some short notes on how to compile the latest OpenDV [1] software on a Raspberry Pi running Raspbian (Jessie). As I learned from the irdDDBGateway newsgroup the latest versions of OpenDV link against libwx 3.0 instead of 2.8. So it is basically installing the required libraries and then compile OpenDV.
Besides the Raspbian OS you need to install the required libs to successfully compile ircDDBGateway and DStarRepeater.
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➔ Handcrafted MMDVM Adapter
| 4 minute read
During experiments with digital voice mode in hamradio I discovered a nice project describing an adapter for D-Star, DMR and other digital modes based on an Arduino Due and a little PCB to be put on top. This unit is called the Multimode Digital Voice Modem or MMDVM (see [1]). It seems that this is getting quite popular because hard- and software is Open Source.
The units can be ordered from Bruce, VE2GZI for a very reasonable price.
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➔ ICOM ID-51 data cable
| 2 minute read
After getting an ICOM ID-51 as a replacement for the IC-92 I had a look at the data jacket of the radio. It can be used to control it via CI-V or configure it using the original OPC-2218LU data cable. The original part is about 60€ here in Germany - a little to expensive for what is contained.
Decompressing the driver archive for this data cable revealed a .cab file which itself contained a driver that is obviously used for PL2303HX USB serial adapters.
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➔ Correcting PitS ADC converter
| 2 minute read
For a balloon mission we bought a Pi-in-the-Sky Board from [1] and put it together with a Raspberry Pi A+. The board offers some ADC converter in order to measure input voltage and current. These values are then sent to ground using the onbard SSDV transmitter. Our board is revision 2.4 and suffering from an overdriven input to the ADC converter.
The input voltage is fed to the ADC converter using a voltage divider consisting of R12 and R13 in the schematics.
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➔ Setting up an XReflector
| 3 minute read
After fiddling around with some D-Star stuff I came to setting up an own D-Star reflector using dxrfd. As that is basically just some C program to compile there is some stuff to do to get it running as a service. My one is running on a server hosted at a German data center running Ubuntu 14.04 LTS at the moment. To set all this up there are several things to consider from logging up to refreshing the dashboard values
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