I have a rather poor quality but full size print of a printed circuit
board I wish to duplicate. It's on cheap thin paper with printing on the
other side. My scanner gives the best results when using grey rather than
B&W. But of course shows the print on the other side. And the edges of the
tracks are pretty ragged.

Of course I could just use this as a guide and draw an entire new
one - but wondered if it was possible to clean up the track edges and
produce only B&W in software?

--
*Keep honking...I'm reloading.

Dave Plowman London SW
To e-mail, change noise into sound.

On 9 Apr, 10:11, "Dave Plowman (News)" wrote:

*Of course I could just use this as a guide and draw an entire new
one - but wondered if it was possible to clean up the track edges and
produce only B&W in software?

Of course. However that's just reducing the colour depth, not
straightening the edges. An edge detection filter can be useful for
that,although it will change the proportions a little. Best of all
(complicated, but allows editing afterwards) is to import the bitmap
into an SVG editor like Inkscape and then convert it all to line
segments.

Dave Plowman (News) wrote:
I have a rather poor quality but full size print of a printed circuit
board I wish to duplicate. It's on cheap thin paper with printing on the
other side. My scanner gives the best results when using grey rather than
B&W. But of course shows the print on the other side. And the edges of the
tracks are pretty ragged.

Of course I could just use this as a guide and draw an entire new
one - but wondered if it was possible to clean up the track edges and
produce only B&W in software?

yes, but you will still have to touch it up.

quick trace over job is far better.

Andy Dingley
wibbled on Friday 09 April 2010 10:52

On 9 Apr, 10:11, "Dave Plowman (News)" wrote:

Of course I could just use this as a guide and draw an entire new
one - but wondered if it was possible to clean up the track edges and
produce only B&W in software?

Of course. However that's just reducing the colour depth, not
straightening the edges. An edge detection filter can be useful for
that,although it will change the proportions a little. Best of all
(complicated, but allows editing afterwards) is to import the bitmap
into an SVG editor like Inkscape and then convert it all to line
segments.

If you were going to do that, might as well download Eagle PCB softaware
(it's free for limited sized boards) and copy the design. It's got a fairly
small learning curve and does a nice job.

--
Tim Watts

Managers, politicians and environmentalists: Nature's carbon buffer.

On Apr 9, 9:11 pm, "Dave Plowman (News)" wrote:
I have a rather poor quality but full size print of a printed circuit
board I wish to duplicate. It's on cheap thin paper with printing on the
other side. My scanner gives the best results when using grey rather than
B&W. But of course shows the print on the other side.

Put a sheet of black paper on the other side when scanning. That will
hide the printing. Unless your scanner has a black lid like mine!

On 09/04/2010 10:11, Dave Plowman (News) wrote:
I have a rather poor quality but full size print of a printed circuit
board I wish to duplicate. It's on cheap thin paper with printing on the
other side. My scanner gives the best results when using grey rather than
B&W. But of course shows the print on the other side. And the edges of the
tracks are pretty ragged.

Of course I could just use this as a guide and draw an entire new
one - but wondered if it was possible to clean up the track edges and
produce only B&W in software?

Inkscape can trace a greyscale image into vector format.

http://wiki.inkscape.org/wiki/index.php/Potrace

In article
,
Matty F writes
On Apr 9, 9:11 pm, "Dave Plowman (News)" wrote:
I have a rather poor quality but full size print of a printed circuit
board I wish to duplicate. It's on cheap thin paper with printing on the
other side. My scanner gives the best results when using grey rather than
B&W. But of course shows the print on the other side.

Put a sheet of black paper on the other side when scanning. That will
hide the printing. Unless your scanner has a black lid like mine!

This has worked for me, a non-glossy black like sugar paper being best.
--
fred
FIVE TV's superbright logo - not the DOG's, it's ********

On Fri, 09 Apr 2010 10:11:34 +0100, "Dave Plowman (News)"
wrote:
I have a rather poor quality but full size print of a printed circuit
board I wish to duplicate. It's on cheap thin paper with printing on the
other side. My scanner gives the best results when using grey rather than
B&W. But of course shows the print on the other side. And the edges of the
tracks are pretty ragged.

Of course I could just use this as a guide and draw an entire new
one - but wondered if it was possible to clean up the track edges and
produce only B&W in software?


To get a better scan, cover the page with a sheet of black paper.

This will help to eliminate, or at least reduce any "print-through"
from the printing on the back of the scanned page.

Dave Plowman (News) wrote:
I have a rather poor quality but full size print of a printed circuit
board I wish to duplicate. It's on cheap thin paper with printing on the
other side. My scanner gives the best results when using grey rather than
B&W. But of course shows the print on the other side. And the edges of the
tracks are pretty ragged.

Of course I could just use this as a guide and draw an entire new
one - but wondered if it was possible to clean up the track edges and
produce only B&W in software?

Put the print on the scanner and place a piece of black paper/ card over
the top of it and see how it comes out. Something like photoshop can
improve the contrast of the scan.

Dave

On Fri, 09 Apr 2010 10:11:34 +0100, Dave Plowman (News) wrote:

Of course I could just use this as a guide and draw an entire new
one - but wondered if it was possible to clean up the track edges and
produce only B&W in software?

Depends how straight you want your edges. Scan at a high resolution,
300dpi, and when you convert to B&W they may well straigten enough.
Your program to do the B&W conversion really needs the abilty to
adjust at what level in the grey scale the transistion from black to
white occurs with a WYSIWYG preview of the result.

--
Cheers
Dave.

Dave wrote:
Dave Plowman (News) wrote:
I have a rather poor quality but full size print of a printed circuit
board I wish to duplicate. It's on cheap thin paper with printing on the
other side. My scanner gives the best results when using grey rather than
B&W. But of course shows the print on the other side. And the edges of
the
tracks are pretty ragged.

Of course I could just use this as a guide and draw an entire new
one - but wondered if it was possible to clean up the track edges and
produce only B&W in software?

Put the print on the scanner and place a piece of black paper/ card over
the top of it and see how it comes out. Something like photoshop can
improve the contrast of the scan.

Dave
scanning in colour may be even better.

then maybe a bit of blur, to thicken the lines,
then adjust levels, delete most of the light grey
then another blur,
then adjust levels, delete the lighter lines
?

Photoshop bible is the book i learnt most of my tricks from.

"Dave Liquorice" wrote in message
ll.co.uk...
On Fri, 09 Apr 2010 10:11:34 +0100, Dave Plowman (News) wrote:

Of course I could just use this as a guide and draw an entire new
one - but wondered if it was possible to clean up the track edges
and
produce only B&W in software?

Depends how straight you want your edges. Scan at a high resolution,
300dpi, and when you convert to B&W they may well straigten enough.
Your program to do the B&W conversion really needs the abilty to
adjust at what level in the grey scale the transistion from black to
white occurs with a WYSIWYG preview of the result.

--
Cheers
Dave.




Look at http://www.platincnc.com/ , an Austrian chap who has
developed a program to scan pictures and images of PCs and turn them
into useful output. I've used it and it does work.

AWEM

In article ,
Tim Watts wrote:
Andy Dingley
wibbled on Friday 09 April 2010 10:52

On 9 Apr, 10:11, "Dave Plowman (News)" wrote:

Of course I could just use this as a guide and draw an entire new
one - but wondered if it was possible to clean up the track edges and
produce only B&W in software?

Of course. However that's just reducing the colour depth, not
straightening the edges. An edge detection filter can be useful for
that,although it will change the proportions a little. Best of all
(complicated, but allows editing afterwards) is to import the bitmap
into an SVG editor like Inkscape and then convert it all to line
segments.

If you were going to do that, might as well download Eagle PCB softaware
(it's free for limited sized boards) and copy the design. It's got a
fairly small learning curve and does a nice job.

I've got my own PCB drawing software based around a development of Acorn
Draw. For the things I do it's fine. I don't really do enough to make it
worthwhile learning a dedicated PCB prog. And Draw gets used for other
things.

--
*Time is the best teacher; unfortunately it kills all its students.

Dave Plowman London SW
To e-mail, change noise into sound.

On 09/04/2010 10:11, Dave Plowman (News) wrote:
I have a rather poor quality but full size print of a printed circuit
board I wish to duplicate. It's on cheap thin paper with printing on the
other side. My scanner gives the best results when using grey rather than
B&W. But of course shows the print on the other side. And the edges of the
tracks are pretty ragged.

Of course I could just use this as a guide and draw an entire new
one - but wondered if it was possible to clean up the track edges and
produce only B&W in software?


Last time I made PCBs, I found the density of the laser printing toner
onto acetate sheets too poor for etching. Perhaps inkjets fare better.

I ended up filling it in by hand using a marker pen, and using a stanley
blade to scratch off unwanted spots etc from the acetate.

( However, I was copying an original board by *photocopying* the copper
side and then hand-reworking the transparency! FWIW, it was a NAIM 250
power amp which I cloned for a tri-amp setup! )

--
Ron

In article ,
Ron Lowe wrote:
Of course I could just use this as a guide and draw an entire new
one - but wondered if it was possible to clean up the track edges and
produce only B&W in software?


Last time I made PCBs, I found the density of the laser printing toner
onto acetate sheets too poor for etching. Perhaps inkjets fare better.

Funny you should say that. My original inkjet - a Epson Stylus - gave
denser blacks than my current Canon i865 - which uses two black tanks. But
it's slightly denser than my el cheapo B&W Samsung laser. However, tracing
paper gives better results using the laser.

I ended up filling it in by hand using a marker pen, and using a stanley
blade to scratch off unwanted spots etc from the acetate.

I've got some of that iron on stuff to try next.

--
*Show me a piano falling down a mine shaft and I'll show you A-flat miner*

Dave Plowman London SW
To e-mail, change noise into sound.

On Sun, 11 Apr 2010 18:36:23 +0100, Ron Lowe wrote:

On 09/04/2010 10:11, Dave Plowman (News) wrote:
I have a rather poor quality but full size print of a printed circuit
board I wish to duplicate. It's on cheap thin paper with printing on the
other side. My scanner gives the best results when using grey rather than
B&W. But of course shows the print on the other side. And the edges of the
tracks are pretty ragged.

Of course I could just use this as a guide and draw an entire new
one - but wondered if it was possible to clean up the track edges and
produce only B&W in software?


Last time I made PCBs, I found the density of the laser printing toner
onto acetate sheets too poor for etching. Perhaps inkjets fare better.

The trick is to use tracing paper instead of acetate - use heavy stuff =90gsm to avoid crinkling in
the fuser. See my page www.electricstuff.co.uk/pcbs.html for more infop on making good homebrew
PCBs.

In article ,
Mike Harrison wrote:
Last time I made PCBs, I found the density of the laser printing toner
onto acetate sheets too poor for etching. Perhaps inkjets fare better.

The trick is to use tracing paper instead of acetate - use heavy stuff
=90gsm to avoid crinkling in the fuser. See my page
www.electricstuff.co.uk/pcbs.html for more infop on making good homebrew
PCBs.

Nice to hear from the horses mouth as it were - I'd already come across
your site.

I used to get decent transparencies with my old inkjet - but not with
this one. Although there is a difference - it's being printed via a PC
rather than direct from the RISC OS machine the artwork originated on,
because there aren't suitable RISC OS drivers for modern printers. I'm
going to try printing direct from the PC after transferring the files via
PDF. But will try tracing paper - have ordered up your recommendation
from Viking.

I've already tried printing direct from the PC to the cheap laser onto an
acetate and that's rubbish, holding it up to the light. Is it likely to be
better going to tracing paper?

Any guidelines for exposure times between transparency to tracing paper?
My UV box gives the best results at 8 minutes with transparencies.

--
*Ambition is a poor excuse for not having enough sense to be lazy *

Dave Plowman London SW
To e-mail, change noise into sound.

On Mon, 12 Apr 2010 10:31:18 +0100, Dave Plowman (News) wrote:

I've already tried printing direct from the PC to the cheap laser onto
an acetate and that's rubbish, holding it up to the light. Is it likely
to be better going to tracing paper?

Depends on what controls your laser has for the amount of toner
deposited, fuser temperature and transfer voltage. My HP Colour
Laserjet CP1515n has at least 5 settings for each accessable via it's
web interface.

--
Cheers
Dave.

On 11 Apr, 18:36, Ron Lowe wrote:
On 09/04/2010 10:11, Dave Plowman (News) wrote:

I have a rather poor quality but full size print of a printed circuit
board I wish to duplicate. It's on cheap thin paper with printing on the
other side. My scanner gives the best results when using grey rather than
B&W. But of course shows the print on the other side. And the edges of the
tracks are pretty ragged.

* Of course I could just use this as a guide and draw an entire new
one - but wondered if it was possible to clean up the track edges and
produce only B&W in software?

Last time I made PCBs, I found the density of the laser printing toner
onto acetate sheets too poor for etching. * Perhaps inkjets fare better..

I ended up filling it in by hand using a marker pen, and using a stanley
blade to scratch off unwanted spots etc from the acetate.

( However, I was copying an original board by *photocopying* the copper
side and then hand-reworking the transparency! * FWIW, it was a NAIM 250
power amp which I cloned for a tri-amp setup! )

--
Ron

How much did a clone NAP 250 cost to build?

In article o.uk,
Dave Liquorice wrote:
I've already tried printing direct from the PC to the cheap laser onto
an acetate and that's rubbish, holding it up to the light. Is it
likely to be better going to tracing paper?

Depends on what controls your laser has for the amount of toner
deposited, fuser temperature and transfer voltage. My HP Colour
Laserjet CP1515n has at least 5 settings for each accessable via it's
web interface.

It's a cheap mono Samsung - ML-2240.

There is an adjustment for paper types - dunno what that actually does,
and normal lighter darker.

--
*If you don't like the news, go out and make some.

Dave Plowman London SW
To e-mail, change noise into sound.

On 12/04/2010 12:43, Part timer wrote:


( However, I was copying an original board by *photocopying* the copper
side and then hand-reworking the transparency! FWIW, it was a NAIM 250
power amp which I cloned for a tri-amp setup! )

--
Ron

How much did a clone NAP 250 cost to build?

It was over 10 years ago, and I built 3 matching ones to drive my active
Isobariks.

Roughly, the costs would be in the following ballpark I think:

Torroidal xfmr: £50
Main reservoir electrolytics : £30
Case: £50
Output devices: 8 x £10?
Other parts: nominal

Estimate say £250 each.

I once posted some photos of them, let's see...

http://www.lowe-family.me.uk/d-i-y/DSCF1278.JPG
http://www.lowe-family.me.uk/d-i-y/DSCF1279.JPG
http://www.lowe-family.me.uk/d-i-y/DSCF1281.JPG
http://www.lowe-family.me.uk/d-i-y/DSCF1282.JPG
http://www.lowe-family.me.uk/d-i-y/DSCF1283.JPG
http://www.lowe-family.me.uk/d-i-y/DSCF1284.JPG
http://www.lowe-family.me.uk/d-i-y/DSCF1285.JPG
http://www.lowe-family.me.uk/d-i-y/DSCF1286.JPG

--
Ron

On Apr 12, 7:35*pm, Ron Lowe wrote:
On 12/04/2010 12:43, Part timer wrote:

How much did a clone NAP 250 cost to build?

It was over 10 years ago, and I built 3 matching ones to drive my active
Isobariks.

Roughly, the costs would be in the following ballpark I think:

Torroidal xfmr: £50
Main reservoir electrolytics : £30
Case: £50
Output devices: 8 x £10?
Other parts: nominal

Estimate say £250 each.

I once posted some photos of them, let's see...

http://www.lowe-family.me.uk/d-i-y/D...y/DSCF1286.JPG

--
Ron

Interesting. I've sometimes dreamed of making a power amp for the hell
of it (I have pre-outs) but will probably never get round to building
one.

In article
,
Part timer wrote:
Interesting. I've sometimes dreamed of making a power amp for the hell
of it (I have pre-outs) but will probably never get round to building
one.

Maplin used to do an excellent 150 watt mosfet amp for not a lot. Just add
power supply. I've got a pair in the workshop driving home made speakers
which still delight.

--
*Speak softly and carry a cellular phone *

Dave Plowman London SW
To e-mail, change noise into sound.

On 12 Apr, 23:40, "Dave Plowman (News)" wrote:

Maplin used to do an excellent 150 watt mosfet amp for not a lot.

Used to 8-(

I must have built about 50 of those, many of them with paralled output
stages for stage use. Cracking good design, decent performance, even
for hi-fi and unburstable.

In article
,
Andy Dingley wrote:
On 12 Apr, 23:40, "Dave Plowman (News)" wrote:

Maplin used to do an excellent 150 watt mosfet amp for not a lot.

Used to 8-(

I must have built about 50 of those, many of them with paralled output
stages for stage use. Cracking good design, decent performance, even
for hi-fi and unburstable.

Maplin used to do several in house kits which were very good. Was told
they discontinued them because of needing CE marking or whatever. Or
perhaps they preferred to just sell mobile phone cases...

--
*He who dies with the most toys is, nonetheless, dead.

Dave Plowman London SW
To e-mail, change noise into sound.