Date   : Wed, 24 Dec 1997 16:59:10 +0000
From   : Crispin Boylan <viewtronix@...>
Subject: Hard drive part no's.

hi

On the parts list on the Harddrive.zip file on the BBC lives! Website, the
numbers are not shown on the PCB layouts, how can I find out?  I need to
know which socket IC1 is etc,.

I have found prices for most of the parts from CPC and Grandata catlogues,
and it comes to around £15.

How much would the double sided coper-clad board cost?  I also need ferric
chloride, and a UV light source don't I?

These are the steps that I think you need to do to make the circuit board.

1. Buy double sided copper clad board (obviously!)

2. Cover both sides of board in photo-resist fluid.

3. Cover both sides of board with the negative images of the circuit. How
do I line both sides up?

4. Expose both sides of board to UV light source

5. The uv light should make the photo resist fluid hardened on the places
where the copper tracks should be, and then the board should be washed, to
rid it off the unhardened photo-resist fluid.

6. The board should be washed in Ferric Chloride for 5-10 minutes, this
takes off all of the unwanted copper.

7. Wash board again, and the whole thing should be ready, apart from the
holes in the relative positions on the board, once the holes have been
made, the board is ready for component assembly.

Is this right or just a load of rubbish, that is, as far as I can remember
a good way to make circuit boards.  

How difficult is it to do the board making by hand? I know that the two
prints would need to be lined up, but to how much accuracy?  I suppose the
Copper board is where the other £20 cost is! :)

How would this device work with an SCSI hard drive, when it has no actual
controller on board?  Do SCSI devices contain controllers as well, like the
IDE drives?  
See ya!
Crispin Boylan
viewtronix@...
http://easyweb.easynet.co.uk/~viewtronix
"If there's a bright centre to the universe, we're on the planet that is
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