At 02:34 07-05-98 +0100, ard(a)p850ug1.demon.co.uk (Tony Duell) wrote: The H-88 (not Z-88) was a converted H-/Z-19 terminal. I never heard of a 'Z'-88. Do you own or have seen a H/Z-89-90-like machine marked Z-88? Recall I stated that the H-89/Z-90 was built in the same case as the H/Z-19 essentially making a single-unit computer with terminal. Kind of handy since the Z-90 machines were often sold to business owners who had small-size offices or whatever. Anyway, Heath Company offered a kit (have to lookup the model number in my old Heath catalog collection -think it was H88-1) consisting of boards, sheet metal, cables, etc. to make a bare-bones H-89, typicaly dubbed H-88. Yes, a cassette interface was available, maybe with this bare-bones thing and/or a stipped down actual H-89. The earliest floppy disk system for the 8-bitters was the model H-17 used with the H-8. Used the hard sectored Siemens 5.25" floppy drives (1,2 or 3 drives in the case) with an H-17 controller. The H/Z-77 was the soft-sectored 5.25" floppy disk system with 1 or 2 drives and was offered first with the H-89 and Z-90. In addition to the 5.25 systems, and less likely to find because of their original high cost and lousy reliability, was the H/Z-47 8" drive system. I can't recall at this time, as I don't own one, the brand of drives but there was a master floppy drive and a slave floppy drive -used an early SASI knock-off as interface IIRC. Also, the H/Z-67 fixed disk system was offered. I think it was only a 5 MB hard disk IIRC. I can check this stuff if anybody interested as I have most of the manuals for this stuff and some catalogs and other docs. Anyway, the H-8 could use any of these drive systems and the H/Z-89/90 the same. There was quite a bunch of us back in the old days who were a close-knit users group for the H-8, H/Z-89/90 and H/Z-100 machines. It supported a cottage industry somewhat smaller than that of the Apple and Commodore folks, but there were the truly faithful supporters out there and Heath supported us as well. --Chris -- --

At 19:17 07-05-98 +0100, Tony Duell <ard(a)p850ug1.demon.co.uk> wrote: Never was a 'Z'-89. The differentiation between Heath/Zenith using the 'H' or 'Z' in the model name is thus: Only Heath-branded items, whether they be kit or factory assembled, had an 'H' model number (H-77, H-89, H-19, H-110, etc,). Zenith-branded items on the other hand had a 'Z' model number (Z-77, Z-90, Z-19, Z-110, etc.) and were exclusively factory assembled and sold through third-party retailers or more usually, VARs (Value Added Retailers). VARs had either exclusive or shared rights to sell ZDS equipment in a certain geographic region. Heath Company stores handled Heath-branded items along with, of course, their catalog sales and rarely ZDS-branded items. Now notice that there is an 'H'-89 and a 'Z'-90. These were machines that were mostly the same except for a few changes in the floppy disk hardware, etc. mentioned previously in this thread. Hence, the usage of the -89 and -90 numbers to apparently help differentiate between the two systems as far as available software media is concerned. Refering to Tony's statement again: ">The Z-89 is also a converted Z-19, at least at the hardware level. Or at should have been the H-88 but I'm trying to recall from increasingly fuzzy memory on that. I will look that up sometime soon as I was quite interested at one time to get one of the last available conversion kits from Heath to convert an extra Z-19 terminal I had then (actually, still have) to an H-89-like machine. Still have the catalog, I think, which shows that kit. I do vaguely recall something about ROM differences between the very early H-89's and later ones and this cassette thing was the major diff. IIRC. Yes, Heath provided virtually *everything*! I think even PAL listings were provided with the H/Z-100 machines along with its thick monitor ROM listing. Will have to check my H/Z-100 technical manuals on this too. (Boy, I'm piling up a bunch of notes of stuff to look up based on this thread.) Regatds, Chris -- -- Christian Fandt, Electronic/Electrical Historian Jamestown, NY USA Member of Antique Wireless Association URL: http://www.ggw.org/freenet/a/awa/