Wednesday, May 30, 2018

How to program and configure the Zastone D900 DMR radio.

How to program and configure the Zastone D900 DMR radio. (mototrbo)

Zastone D900 DMR (mototrbo)
Please not the programing cable is different to generic programing cables but microphone connections is the same as generic Microphones.

First Download the following application from TYT web
http://www.tyt888.com/?mod=download
Download MD-380
Go into unrared directory "MD-380 software\Firmware 2.30 and new programming siftware"
This file is also available here but could be old if  http://www.giga.co.za/Kit_Drivers/TYT_MD-380_20160908101439.rar

Then untarrar  MD-380(Tytera).rar
The directory then should look like this
UNRAR "MD-380(Tytera).rar"
After the unrar then run the MD-380(Tytera).exe


Continio installation using default settings.
After installation is complete there should be a Tytera MD-380

Run Application Tytera MD-380 in start menu
You should then see the following default screen.
Default Configuration screen
Now download the codeplug for South Africa Repeaters from Here http://www.giga.co.za/Kit_Drivers/Zastone_D900_Code_plug_v1_30_may_2018.rdt
Now load the code plug "Zastone_D900_Code_plug_v1_30_may_2018.rdt"

Load "Zastone_D900_Code_plug_v1_30_may_2018.rdt"
Now edit the DMR radio configuration as required.
Pres green button to download from Radio Red to load to Radio and Blou to save your configeration

Monday, May 21, 2018

How to Create a Linear Transponder using a RTL Dongle and HackRF with Gnu Radio.

How to Create a Linear Transponder using a RTL Dongle and HackRF with Gnu Radio.

I wanted to test the concept of a linear Transponder and how difficult would it be to build it with conventional components.
Hardware Configuration
Hardware required to build the Transponder.
  1. SDR IQ demodulator with rtl dongle (RF In)
  2. SDR IQ DSP processing system. Gnu Radio (DSP processing)
  3. SDR IQ Modulator. HackRF (RF Out)
  4. Background management system. (OBC) for additional telemetry.
Software required for Transponder.
  1. SDR IQ demodulator. rtl dongle (RF In)
  2. SDR IQ DSP processing system. Gnu Radio (DSP processing)
  3. SDR IQ Modulator. HackRF (RF Out)
  4. Background management system. (OBC)

Video of working Transponder.



Gnu Radio.


Transponder Block Diagram

RTL SDR Block.

RTL-SDR Source

Low Pass Filter Block.

 
Low Pass Filter Block

AGC Block.

AGC Block

Power Squelch.

Power Squelch

Osmocom Sink. (HackRF)

Osmocom Sink (HackRF)

FFT. (Spectrum View of input)

FFT Spectrum View

REF: Power point Slides at AMSAT SA

Ref:Source code is available on Github Version 4