It is designed to manage the switchings in a small ATV station operated with a homebrewed FM 2,3 GHz transmitter, but the principles described can easily be adapted for other environments.
On the video side, it is planned a pattern generator input, plus four camera inputs, including one on front panel. On the audio side, a 1000 Hz tone generator and three audio inputs, including one on front panel. A potentiometer makes it possible to set up the audio level.
The video signals and audio signals can be switched on and off independently. The 6.5 MHz subcarrier generator can be switched off. Lastly, the control box carries out the assembly of the multiplex video + audio subcarrier which is then sent directly to the 2.3 GHz transmitter input.
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