8 Jun
2006
8 Jun
'06
1:23 a.m.
> If some others would chip in on the
shipping, I'd gladly send you a
> scanner. Would you prefer SCSI or "Centronics"?
On Wed, 7 Jun
2006, Tony Duell wrote:
I don't care, provided it comes with
schematics and uses chips that I
recognise :-)
I kinda doubt that even the old HP scanners had schematics available. However, the operation of a scanner is not too complex
to reverse
engineer.
Rather you than me. The only scanner I looked inside had several
unindentifyable ICs...
I guess that we still can't get you to accept one,
even for free, without
open hardware source.
Surely you all know me by now. I am not going to depend on something
that I can't repair.
Does it
_depend_ on the mains frequency? Votlage conversion is trivial (I
have a 110V step-down transformer in the workshop anyway), frequency
conversion can be more of an 'interesting' job.
I'd be tempted to do it "mechanically", with a motor and generator. 8" drives may need 50 v 60 Hz (or a change of
pulley and belt).
Making a new pulley is not a particularly difficult job....
But almost everything else recently is rectified to
DC.
Most "modern" computers just want 5VDC, 12VDC, etc.
Indeed. Occasionally, the mains frequecy was used for a real time clock (in
which case the thing won't keep good time, which may not be a big problem
-- if it is, a crysal + divider chain would be a workaround). Very
occasionally, the transformer is rated only for 60Hz (higher frequency
means you can use a smaller core for the same power, that's (a) why a lot
of aircraft stuff ran at 400Hx, and (b) why the transformers in SMPSUs
are small). But most trasnformers that are used on 60Hz are OK for 50Hz
too.
-tony