Xref: utzoo rec.ham-radio:3870 sci.electronics:2075
Path: utzoo!utgpu!water!watmath!clyde!rutgers!ucsd!brian
From: brian@ucsd.EDU (Brian Kantor)
Newsgroups: rec.ham-radio,sci.electronics
Subject: Re: build-it-yourself EPROM erasers
Message-ID: <12@ucsd.EDU>
Date: 9 Feb 88 17:42:55 GMT
References: <8802091255.AA23298@ucbvax.Berkeley.EDU>
Reply-To: brian@ucsd.edu (Brian Kantor)
Organization: UCSD wombat breeding society
Lines: 42

Easy to do.  Go to a LARGE industrial electrical, restaurant,
laundry, or hospital/sickroom supply house and buy an ultraviolet
GERMICIDAL LAMP.  This will be a small clear fluorescent-style lamp 
tube.  They are typically available in either 15 or 25 watt sizes.

You will also need the two SOCKETS that it mounts in, and the BALLAST
that must be wired in series with it, a starting pushbutton
(any normally-open pushbutton rated for 115VAC will do fine - there's
very little current here), and a safety interlock switch.

I haven't priced this stuff recently, but I'd guess that it's on the
order of $20 or so.

Find a box that it will fit in that is OPAQUE and has an easily
removable lid.  I used an 8-track cartridge storage box from my local
K-mart.  Install the lamp, sockets, ballast, an AC mains power
cord, and for safety, a switch which disconnects power when you open the
lid.  See the crude circuit below.

Put some conductive foam in the bottom of the box so you can put the
EPROMS into the foam within a few inches of the lamp.  It should erase
the bits in about 1/2 hour exposure to the ultraviolet light the
germicidal lamp gives out.

Be careful.  Don't fry your eyes, and be sure to insulate everything
well so you don't zap yourself.
	- Brian


		/  safety interlock	 ballast
    AC -------./ o---------------------()()()()-|
						|
		  ________________________	|
    AC ---------==|=\			/=|==---|
		  | }	lamp		{ |
	      |-==|=/			\=|==---|
	      |	  -------------------------     |
	      |	       ___			|
	      |--------o o----------------------|
			norm-open
			starting
			pushbutton