Unknown TI logic series

The strange number may well have been there to prevent them being resold as full spec 74 series parts. As to TI not selling untested parts. Well go look at a DEC board full of TTL and tell me who made them. Hint DEC 100% tested all bought out semiconductors and in many cases put their own numbers on them. If you have your own testing facility why buy tested parts? Regards ? Rod Smallwood -----Original Message----- From: cctech-bounces at classiccmp.org [mailto:cctech-bounces at classiccmp.org] On Behalf Of Shoppa, Tim Sent: 17 December 2010 19:14 To: cctalk at classiccmp.org Subject: Re: Unknown TI logic series I tend to come in on this side too, these funny series are Effectively TI-supplied "house numbers". They may be different than stock SN7400 TTL or whatever DTL in minor or Major ways but that was an agreement between the customer and TI. I've seen the innards of DTL and TTL based calculators, and to think that They would work with rejects or floor sweepings is unreasonable. If Anything I would think that the house-numbered part would have some specs tightened And others loosened to produce something most manufacturable. And isn't That the reason for house numbers to begin with? (e.g. not purely obfuscation) Tim.