https://worcester.craigslist.org/sys/d/millbury-retro-z80-computer-new-in-bo...
https://publications.gc.ca/collections/collection_2018/mstc-cstm/NM33-1-17-e... large PDF, look at page 53-55 for "Nabu Manufacturing Corporation" of Canada The following is a lecture on the topic of these devices. Discussion of these units, mis-characterizes them as "Z80 systems". They apparently have a Z80, but they are not "systems" in the way an Apple II or a IBM-PC comparable or modern computers are personal computing systems. In my informed opinion, these are artifacts of an era, one that few people today have experienced; and hard to put to more-familiar use. My informed guess - I don't know, they are new to me - is that these are more fuss than most expect. That's the lecture. https://en.wikipedia.org/wiki/Teletext At a time around 1980, there was a confluence of several technologies. One of course was CRT based color TV's. Another, telephone networks, broadcast TV networks, and also early cable TV networks. Another of course, were 8-bit microprocessors. But it was early days in personal computing, and now-common stuff like mass storage, floppy drives as removable storage, and software - and experience with these by ordinary people - was still in short supply. But people understood things, like newspapers, telephone books, and paper-notes-on-cork bulletin boards. They were used to being information consumers, not producers. Businesses "thought" this way at the time. Again: 1980, don't blame me. So a niche that could be filled, was to build a terminal, that relied on a telecom network (wired phone, cable TV, broadcast TV) to broadcast data; display it on a customer's TV; and accept some slow and short data from a customer keyboard. The customer terminal, only needs to intercept some "page" of data among all the pages sent out, over and over again. These services had various brand names, but "teletext" is adequate to describe most of them. They provided information "narrowcast" and broadcast services; thus they had some incoming revenue, even saving costs (like printed telephone books, as in France as I recall). MOst use was outside the USA. Research of/in the era will flesh this all out. And that explains this Nabu. Apparently a Cable TV terminal. No mass storage because all content is "downloaded". No I/O, except maybe a printer to print notes (coupons for shopping, content to read later). No user programs - user's don't know how to program, the content is supplied. It's a *service*, not a computer - in general. But research shows (the PDF link), it did run some games and some "home" programs like "personal finance". It was in use from 1983 to 1986 (I nailed the date not knowing this.) This unit - I haven't seen the insides, it's unfamiliar to me - apparently has some kind of "slots" for some kind of boards. Due diligence may find details, or reverse engineering may determine the interface AND - and, and - a fair amount of disassembly of the onboard ROMs. Either it's already been done, or someone could assess several to make it worth doing. On value. I think comments like "the keyboards are easily worth $20" are, um, speculative. I've pointed out the challenges of the guts of it. Someone (not me) might be moved to provide some leadership on these, to make something more "vintage computer-ish" out of them. A very smart person, might figure out the head-end protocol to "feed" these devices. But they will have to modulate a cable TV frequency to get it into the box; not simple hardware, not digital. There were all kinds of Z80 based devices produced around 1980. They were purpose built, so it's a kind of a puzzle-to-solve to re-purpose them. Parts value? I guess. Historic value? if that's your mission. If someone has dozens, hundreds of them, it becomes an investment of some sort. These are my observations, bits of research, and some opinions I have; I'm informed on some of this. I'm not looking for a discussion or argument, the focus is this pile of devices and what one might DO with them. I'm providing some context to make more informed decisions. regards Herb Johnson -- Herbert R. Johnson, New Jersey in the USA http://www.retrotechnology.com OR .net preserve, recover, restore 1970's computing email: hjohnson AT retrotechnology DOT com or try later herbjohnson AT comcast DOT net