Date   : Thu, 21 Feb 2002 08:46:36 +0000
From   : Mike Tomlinson <mike@...>
Subject: Re: BBC Micro repairs

In article <egSSefDrvCd8EwhW@...>, John Woodgate
<jmw@...> writes

>Watford DFS 1.3.

DFS? Not DDFS?  

Unplug the Beeb and pop the lid off (4 screws, marked 'fix', two at the
back, two underneath at the front) and with the front of the machine
facing you, is there a large 40-pin chip or a raised plug-in module
present in the 40-pin socket on the LHS, two large chips over from the
6502 in the centre of the board and next to two empty 28-pin sockets?

If the chip has the letters "DS8271" or "i8271" present on it, give it a
gentle push into its socket with your thumb.  Do the same for the two
chips immediately below it (marked "7438").

Unplug the disc drive ribbon cable and make sure none of the pins in the
socket on the Beeb are bent.

Take the lid off the disc drive unit and make sure the ribbon cable is
firm and snug on the edge connectors on the back of the drive(s).
Sometimes pulling on the cable can cause the plug to come off the drive
- the method of cable restraint used varied widely from good to none.

> The other Beeb has an Acorn 1770 DFS but it doesn't
>respond to the keyboard.

That's probably just oxidised keyboard cable contacts, a common problem.
Pop the lid off, unplug the keyboard cable at both ends and refit it.
It doesn't matter which way around it goes.

>>2. Does the drive light illuminate and the motor spin when you try to
>>access a disc?
>Yes. 

It's all pretty much working, then.  I doubt the problem is severe -
just a loose or dirty connection, especially if it all worked last time
you used it prior to packing it away (as ISTR you saying you did.)

-- 
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