Operation	Disk	Timing
===============	=======	= =======
Load file:	H/S	12 sec.
	S/S	9
Save file:	H/S	24
	S/S	13

Of course, these timings may vary, depending on your operating system version and hardware.

But one of the fancy additions which Heath included was to make the thing semi-intelligent. You could put a disk with almost any of the recognized formats in a drive and the system would configure itself to read the format. Neat! The only exception (yes, there is one of those!) is that single-tracked drives can't read double-tracked disks. That's because the size of the read/write head on the former bridges two tracks on the latter. However, the reverse can be done.

Implementing the Hardware. Although I've only discussed Heath/Zenith's board so far, there are actually three sources for soft-sector controllers. (Heath is no longer one of them!) In alphabetical order, they are C.D.R., Magnolia Microsystems, and Technical Micro Systems, Inc. (TMSI). The chief disadvantage of the first two is that the necessary system software (device drivers for HDOS and BIOS for CP/M) departs more or less from the "standard" which Heath established for soft-sector on the '89. Moreover, if you are running both operating systems, the driver software for the second system (usually HDOS) costs extra. The other side of the coin is that they may provide you with features (such as access to eight-inch drives) which you want and which the "standard" can't supply.

But that "standard," the Z89-37, is still available from TMSI. This is a functional equivalent to Heath's board. That means you can bring up soft-sector CP/M directly from Zenith's 2.2.03 or .04. For HDOS, you'll need a device driver since the freebie which Heath supplied is no longer available. But because TMSI went to CMOS chips, the board draws only half the current of the original. So the power supply upgrade (which came with the original) is not provided. However, if you've added a lot of hardware to your system, you should do this anyway. (If you need advice, write me; I'm always free with advice! And if you have a question, criticism, or other remark, write. Just don't forget the SASE!)

In the future, I'll cover bringing up system software on soft-sector. If you're running HDDS or Zenith's CP/M, you can do the whole thing yourself! If you have Magnolia's CP/M, you will need some assistance from the vendor. Either way, when you've completed this, you can have a plaque inscribed with your name and the phrase, "SYSTEMS IMPLEMENTOR," hung on the wall behind your equipment! But whichever way you go, you will have a faster system (with higher external storage). And that's the name of the game! And this column!

Backing Up the Hardware. These days, if you run one of Heath's discontinued 8-bit machines, you shouldn't only worry about backing up your soft-

ware. You also should consider backing up your hardware. If you attend one of the HUGCON's, you have the opportunity to pick up various sale items and, of course, local and national newsletters typically include systems for sale. But there is another source if you're interested in single boards or other components.

This is an electronics liquidator, Al Davis, whom I stumbled across while at Midwest HUGCON in St. Louis last May. If you send him a list of your needs, he will ship what he has, COD. Prices are very reasonable ($10 to $25). The only thing you will note on receipt is that boards usually have a hole drilled in them in a noncritical area. This is to mark them as surplus and should not effect usage.

However, if you're running a very old machine like mine, the only boards you will find are for the '89A. But there are significant design differences between the two! For example, some of the connectors are oriented differently, as I noticed the last time I had my system torn down. So I can't just drop in a spare board and expect to fly. I'm currently querying Heath on manuals for the '89A and will let you know how that turns out.

VENDORS MENTIONED:

Al Davis, Electronics Liquidator / 187 Lake Chapin Road / Barrien Springs, MI 49103

C.D.R. Systems / 7210 Clairemont Mesa Blvd. / San Diego, CA 92111 / (619) 560-1272

Magnolia Microsystems, Inc. / 2820 Thorndyke Ave. West / Seattle, WA 98199 / (206) 285-7266

Technical Micro Systems, Inc. / 366 Cloverdale / Ann Arbor, MI 48105 / (313) 994-0784

See you next issue, Kirk L Thompson

THE SEBHC JOURNAL

Another newsletter with raison d'etre similar to THE STAUNCH 8/89'er was born recently. It, too, deals solely with H-8 and H-89-series computers. It is the SEBHC Journal, edited and published by Leonard Geisler. (SEBHC stands for "Society of Eight-Bit Heath Computerists".) The new publication is a monthly, and October marked its third issue. At this writing I have seen the first three issues, and am impressed with the high quality of articles. Subscriptions are $12.50/year. Make checks out to "P.E.S." ("Plain English Services"). The address is; 895 Starwick Drive, Ann Arbor, MI 48105. [Funny thing, perhaps it requires a Geisler to try to reestablish an exchange of 8-bit information. The following coincidence is a case in point: Len Geisler and Hank Lotz are each of Geisler lineage. Len's half, from his paternal side, is obvious. But I also have 50% Geisler blood from my maternal ancestry. — HL.]

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