This articale made me have recoolection of the EDUC 8 from about 1974 built with just TTL chips

https://en.wikipedia.org/wiki/EDUC-8

The EDUC-8 is an 8-bit bit-serial design with 32 to 256 bytes of RAM. The internal clock speed is 500 kHz, with an instruction speed of approximately 10 kHz,

First published in Electronics Australia in August 1974, the EDUC-8 was designed specifically for home construction by electronics hobbyists.