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From: bldrnr@Apple.COM (Brian Hurley)
Newsgroups: sci.electronics
Subject: Re: Kludged Laser Power Supply
Keywords: laser scanning
Message-ID: <41636@apple.Apple.COM>
Date: 5 Jun 90 18:23:52 GMT
References: <5395@jhunix.HCF.JHU.EDU> <2667547f-214.1sci.electronics-1@vpnet.chi.il.us> <5452@jhunix.HCF.JHU.EDU>
Organization: Apple Computer Inc, Cupertino, CA
Lines: 23


Ack, a speaker with a bit of mirror on it?  In some areas it is possible to
find early Pioneer LDP 1000 laser disc players that have a HeNe laser, 
several red-spectrum surface mirrors, a 10mm x 10mm beam splitter, and
a pair of galvos with surface mirrors attached.  These little dudes are
used to position the beam on the surface of the disc.  They are about
8 ohms impedance and work quite well when driven from LM386 audio amps.

The LDP 1000's are usually found at surplus places for between 25 - 99 dollars
depending on where you find them.  

I have a little rig that I have built that uses a Macintosh SE as a sound
source, and a delay pedal(from my electric guitar) to display all kinds
of neeto patterns.  

Don't expect a lot of bandwidth out of the galvos. Above about 500Hz, they are
worthless, nonlinear, and given to making like fuses if driven too hard.

For my $99 it's been a heck of a lot of fun.  Your milage may differ.

- Brian

	bldrnr@apple.com