The 74LS181 in the middle is a 4-bit ALU. Maybe it displays a mathematical result of some sort? -----Original Message----- From: cctalk-bounces at classiccmp.org [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Vintage Computer Festival Sent: Tuesday, July 12, 2005 11:39 AM To: General Discussion: On-Topic and Off-Topic Posts Subject: Re: Mystery box On Tue, 12 Jul 2005, Stefan wrote: Obviously a meter of some sort. Perhapsa histogram? -- Sellam Ismail Vintage Computer Festival ---------------------------------------------------------------------------- -- International Man of Intrigue and Danger http://www.vintage.org [ Old computing resources for business || Buy/Sell/Trade Vintage Computers ] [ and academia at www.VintageTech.com || at http://marketplace.vintage.org ]