Date   : Fri, 15 Jun 2001 20:15:55 +0100
From   : Mike Tomlinson <mike@...>
Subject: Re: Faulty Vicrovitec Monitors

In article <6D293A121957D4119899009027FCB5DE0482DB@...>, Andrew
Chesterton <achester@...> writes

>Can anybody help ?

I fixed BBC Microvitecs for seven years...

>When I power on my BBC the monitor displays about a dozen small horizontal
>lines about 1/3rd of the way down the screen. The lines roughly correspond
>with the first line of text that a BBC normally displays on bootup. From
>memory I think it is the type of DFS installed.

... but this is an unusual fault.  It sounds like a horizontal sync
problem.  Is the image static or rolling?  Flickering?

Was this sudden?  Has the monitor previously worked?  Does it make any
odd noises?  Tried another BBC?  Beep out the RGB cable with a meter -
it should be pin-1-to-pin-1, through to pin-5-to-pin-5.  Pin 6 (the
centre pin) is not used.

The most common fault with Microvitec Cubs were in the power supply and
in the frame circuit (the frame chip is in the back right hand quarter
of the board, and has a heatsink on it, though failure normally results
in frame collapse - a bright horizontal line across the centre of the
screen.)

-- 
"Security-wise, NT is a server with a 'Kick me' sign taped to it."
                      - Peter Gutmann