Homebrew PCBs

Funny how the original Edison Bell phonograph gets updated and changed from sound recording to light recording.

Malcolm

I don't suffer from insanity I enjoy it!
Mene, mene, tekel, upharsin
The writing is on the wall.
Ha-ktovet al ha-kir

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On Thu, 5/1/14, Boman33 <boman33@...> wrote:

 Subject: RE: [Homebrew_PCBs] updated my laser photoplotter
 To: Homebrew_PCBs@yahoogroups.com
 Date: Thursday, May 1, 2014, 4:42 AM
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
  
 
 
 
   
 
 
     
       
       
       I remember your
 laser plotter from you original posting.A great
 project!
  From: elson@...  
 Sent: Wednesday, April 30, 2014 23:21
 
 Well, I finally got around to
 updating the laser photoplotter I built in 1996.  it
 was stillrunning on the creaky Cyrix-CPU ISA-bus PC
 with a DMA card.  I was worried abouthow much
 longer that PC would still run.I replaced it with a
 Beagle Bone, and used the PRU component of that
 processorto emulate the DMA card in the PC.  I
 had a few software bugs that wereembarrassingly hard
 to find, but it now works just fine.It does 1000 x
 1000 DPI and is VERY accurate, I have made solder
 stencilswith it that match within a couple
 thousandths of an inch over an entire  8 x
 12" PC board fabbed in China.  (I use it mostly
 for making the masterartwork to etch solder paste
 stencils, now that PC boards are so cheapfrom
 China.)  Plotting speed is 0.6" per minute, and it
 can do up to20 x 20" films.SeeHomemade Laser
 Photoplotter   for more info.