[TMC] Need software to change blueprint to blackline

[WA5CAB at cs.com]

Groups,

I received a file from another member of several of these lists asking 
whether I could turn several blueprints in to regular black on white.  The parts 
are specifically machinery parts to make but I also acquired recently a 
couple of radio manuals worth scanning with for some strange reason the 
schematics as blueprints.  Hence the wide distribution.

Does anyone know of any software that can turn a scanned negative or 
blueprint into a positive (black lines on white)?  If so, please tell me what it 
is.  I actually thought I had done some of this a few years ago but when I 
went to try to find what I did it with, the cupboard was bare.  It would also 
be nice if the application costs less than AutoCad!

Robert Downs - Houston
wa5cab dot com (Web Store)
MVPA 9480