hamradio station pa2eon

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Aug 27

Raspberry PI as ATV testscreen modulator

Today I updated the Raspberry PI as an ATV testscreen ‘modulator’.
The designer of this solution you can find at the website of PA3BWE.
In this log, I will show the mods, and the short (new) installation options.

Important!

Start with the install of the latest Raspberry OS ( you can find on raspberrypi.org)
In this OS, you will find the python and python-pygame we need for the graphics.

The basic commands:
apt-get update

* Get the ‘atv3.py’ from the website of PA3BWE
* Place this file in the folder you want to use (mkdir /home/pi/atv)
* wget http://www.pa2eon.nl/download/atv.tar
* Make two folders extra
mkdir /home/pi/atv/images
mkdir /home/pi/atv/sounds
* In the images directory you can place about 12 files with a resolution of 768 x 576 pixels.
* In the sound  directory you place the *.wav file you like ( the ‘test-beep’ ..)
* In the directory /home/pi give the command tar xvf atv.tar

Important!

To use the RCA connector (to place the right video signal to your ATV hardware) you have make an config.txt file.
This file you have to place in the /Boot folder of the Raspberry.
The next lines are important to change;
 
overscan_left=-15
overscan_right=-28
overscan_top=-60
overscan_bottom=-25 # To change if characters drop the screen in bottom
#
sdtv_mode=2
arm_freq=700
#
core_freq=250
sdram_freq=400
over_voltage=0
 
After reboot of the py, give the command: sudo python atv3.py

In the download section of this site .. you will find the used file by myself ( and PA3BWE !).
The picture shows the old (green) computer screen, with the RCA active and nice test screen.
Testscreen old wayTest screen oldway 2 Basic text

 

 

 

 

 

 

 

The next weeks I will try to make an *.py program where the ‘graphics’ are generated by the application itself. The pictures shows the original file, and if you want to give more text you are not free to do that. The third picture is the graphic made by the application (atv3.py), very basic but useful !

Note: To test the status off the picture generated by the Pi, give the command; /opt/vc/bin/tvservice -s