vikinguk:
Hi Nikola,
No BC1 does not have electronic curtain. Picture goes off and sound rapidly diminishes afterwards.(I have just acquired BC1). The Avant does. When the screen comes on the picture appears in the centre as a thin vertical line and then opens out to the wide screen. The sound gently comes on (and gently goes down as the curtains close when switching off.) I think an earlier Beovision model actually had a physical electronic curtain with shutters that slid from the centre to left and right.
Dave: Sorry, can't help with the original query re step being missed. Coincidental loss of signal from a STB causing picture loss at same time as switching off?
Vikinguk
On that note though, my BC1's sound fades in and out rather slowly on powering up and down. I'd be curious to know if anyones BC1 has electronic curtains, later versions had the option to have the 5.1 channel powerlinks at the back...
If my set top box looses signal an icon comes up saying "no, or bad signal" It appears my BV3 glitched! As i said i repeated exactly the same with the beo 4, turned the TV back on, pressed AV RADIO and mute (so i can see the radio station on the screen), covered the tip if the Beo4 with my hand and pressed TV, then stand-by. Curtains worked as normal. 
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