The receiver ref. 7243 produces a flickering effect on the screen menu and in the tuned channel.
However, the channel frequency is correct, as the best tuning point has been searched for.
Domestic receivers that feature video switching (*) generate picture flickering when the signal received is near the quality threshold (c/n ratio).
The solution is to:
Improve the c/n ratio by checking the installation:
(*) Those that display a coloured background instead of grain when there is no signal