Hi
RTL is 3.6V. You could get by with CMOS but
not TTL, directly. Of course, you could run two
power rails. The signal levels of RTL and TTL are
somewhat compatable.
Dwight
>From: "Cini, Richard" <RCini_at_congressfinancial.com>
>
>OK, this might sound like a stupid question, but being somewhat ignorant of
>RTL logic in comparison to TTL and other designs, what, if anything, can be
>substituted for RTL logic chips?
>
>For example, if I wanted to build one of Don's devices and I wasn't
>concerned with using "vintage" chips, could I do it "plug-and-play" using
>current TTL?
>
>Rich
>
>-----Original Message-----
>From: cctalk-bounces_at_classiccmp.org
>[mailto:cctalk-bounces_at_classiccmp.org]On Behalf Of Michael Holley
>Sent: Friday, January 07, 2005 12:08 AM
>To: cctalk_at_classiccmp.org
>Subject: RTL Logic
>
>
>I have acquired some Don Lancaster designs that use RTL logic and I am
>looking for spare parts. The MC789 hex inverter is used in all of them and I
>have 2 chips. Does anyone have a reasonable source for the MC789, I can get
>all I want for $20 a chip.
>
>I also have 2 MC799 buffers that are use in the Microlab. I have found two
>each of these (MC725, MC778, MC785, MC792, MC853, MC855) that I will part
>with.
>
>SWTPC Digital Logic Microlab
>http://www.swtpc.com/mholley/PopularElectronics/Apr1970/PE_Apr1970.htm
>Early SWTPC keyboard
>http://www.swtpc.com/mholley/PopularElectronics/Apr1974/PE_Apr1974.htm
>
>I think that Don Lancaster's TIC TAC TOE machine from 1971 is a very clever
>design. It uses 5 ICs and 60 diodes to play the game. I may build one.
>http://www.swtpc.com/mholley/RadioElectronics/Dec1971/RE_Dec1971.htm
>
>Michael Holley
>www.swtpc.com/mholley
>
>
Received on Fri Jan 07 2005 - 11:19:15 GMT