Hmmm... I can see I attached a pic, but it didn't get through.  Sorry about that.  I have posted the pic here:   http://www.tollianweb.com/uc/vti.jpg   It's IC 1N from an Exidy 440 PCB (Whodunit in this case).  I'd really like to identify the manufacturer.  I looked at several IC logo web sites and nothing comes up.  It's in a bank of 2764's and supposedly supposed to be able to be read as a 2764, but my EETools Top Max is unable to read it.  Really a mystery to me why I can't find this symbol at all (and why if it is equivalant to a 2764 my reader can't read it).  It's not a bad chip as the game boots up and passes all self tests without any complaining.   If anyone might be able to identify what IC is on 6K on the same boardset type, that would be appreciated too.  On my board, it's a National 74S28(x) where "x" is either a 7 or an 8, but it's overlayed with an Exidy part number stamp.  National 74S287 crosses to an MMI 6301 (Signetics 82S129) and a 74S288 crosses to a MMI 6331 (Signetics 82S123).   Trying to dump a Whodunit ROM version that's not in MAME.  Thanks,   Joe ________________________________ From: Clay Cowgill <c.cowgill@comcast.net> To: 'Technical Tools Mail List' <techtoolslist@flippers.com> Sent: Monday, November 18, 2013 11:28 PM Subject: Re: [Techtoolslist] Can anyone identify this chip? Hey Joe, The only attachment I received was some text with pointers to John's archives.  Did you forget the attachment or did it get stripped by the time it made it out the mailer? -Clay -----Original Message----- From: techtoolslist-bounces@flippers.com [mailto:techtoolslist-bounces@flippers.com] On Behalf Of Joe Magiera Sent: Monday, November 18, 2013 9:24 PM To: Techtoolslist@flippers.com Subject: [Techtoolslist] Can anyone identify this chip? Can anyone identify the chip in the attached picture?  I cannot find the manufacturer's symbol or anything related to VTI.  I found one source of VTI mentioning being acquired by Murata.  I wrote to them and they told me it was a different VTI.  It's in a bank of 2764's, but my EETools Top Max can't read it as a 2764. I would really like to find the manufacturer's name.  Thanks, Joe _______________________________________________ Techtoolslist mailing list Techtoolslist@flippers.com http://seven.pairlist.net/mailman/listinfo/techtoolslist FTP site is: ftp://ttl.arcadetech.org/TTL/Test_Equipment Archive site: http://seven.pairlist.net/pipermail/techtoolslist/ _______________________________________________ Techtoolslist mailing list Techtoolslist@flippers.com http://seven.pairlist.net/mailman/listinfo/techtoolslist FTP site is: ftp://ttl.arcadetech.org/TTL/Test_Equipment Archive site: http://seven.pairlist.net/pipermail/techtoolslist/