PMR Frequency
Band: 446.0–446.2 MHz
Analog PMR446 uses narrow FM in a 12.5 kHz raster, 16 channels.
dPMR uses FDMA in a 6.25 kHz raster, 32 channels.
dPMR -> NXDN -> 4FSK/FDMA
Used by Icom IC-U20SR
PMR446 DMR (Tier 1) uses TDMA in a 12.5 kHz, 16 channels.
Both digital codes uses 4-level FSK modulation at 3.6 kbit/s
Source: https://en.wikipedia.org/wiki/PMR446
Complete overview in Dutch:
https://www.groveld.com/articles/pmr-frequencies
https://www.rtlsdr.nl/pmr-446mhz
ICOM CS-F52D programming software – add zone
Question: Can I add multiple zones to ICOM F52D and F62D NXDN handheld radios? I currently only have one zone, and I can’t figure out how to add more.
Answer: To add a zone, the Capacity field needs to be entered first. See the screenshot of the CS-F52D programming software. This information is missing from the help file and documentation.
RTL-SDR Calibration with R820T2 chip
Calibrating your DVB-T dongle with R820T(2) chip
First: Installation of RTL-SDR
sudo apt-get update
sudo apt-get install cmake build-essential libusb-1.0-0-dev
cd ~
git clone git://git.osmocom.org/rtl-sdr.git
cd rtl-sdr
mkdir build
cd build
cmake ../ -DINSTALL_UDEV_RULES=ON -DDETACH_KERNEL_DRIVER=ON make
sudo make install
sudo ldconfig
Second: Installation of kalibrate-rlt
cd ~/src
sudo apt-get install libtool autoconf automake libfftw3-dev
git clone https://github.com/asdil12/kalibrate-rtl.git
cd kalibrate-rtl
git checkout arm_memory
./bootstrap
./configure
make
sudo make install
Make sure the RTL stick is running for few minutes to let it warm-up. Get a first rough ppm offset estimation with: Read more
Kenwood TH-D7 Memory Control Program
I’ve made some preset configuration files for the Kenwood TH-D7.
Read more
Kenwood TM-D700 Repeater audio fix
The Kenwood TM-D700 got a modification to enable repeater mode. Once done, you’ll find out the transmitted audio is not filtered well. After some research I’ve found this kenwood service bulletin and decided to give it a go and the result Read more
