Date   : Sat, 21 Apr 2012 23:00:10 +0100
From   : walker_matt@... (Matt Walker)
Subject: Video Problems

Thanks for the info Peter.

VDU 7 and PRINT CHR$(7) both make the beep, as they should. It beeps after a 
CTRL-BREAK too.

MODE7:!&7C01=-1 moves the cursor to the top left, like CLS

Also discovered that leaving it on for a while makes loads of rubbish 
(mostly long horizontal white lines) appear on screen (as a chip gets hot?)

And replacing the CRTC does nothing