A&J Micro Drive
Owner(s):
Jim Howell
1050 East Duane Ave., Suite I, Sunnyvale, CA 94086
A&J Micro Drive was a spin-off of Exatron, the company that manufactured and marketed the Exatron Stringy Floppy (ESF). The Exatron Stringy Floppy was a continuous loop tape cartridge (“wafer”) that had some advantages over traditional cassette tapes.
Exatron also manufactured the tape drive mechanism and sold it via mail order to home computer owners. The first ESF drives were made for the TRS-80 Model I. Wafers were available in several lengths, from 5 feet (which could store 4K of data) to 75 feet (up to 64K).
By 1983, Exatron needed additional capital to improve the overall performance and quality of the wafer drives and wafers. With new investors came the name change to Entrepo (a word close to the French word for warehouse). Exatron focused on large OEM accounts and Jim Howell, son of the Exatron founder, took over the mail-order stringy floppy business with his company, A&J Micro Drive.
One investor, BSR Ltd., the Hong Kong-based electronic components and consumer electronics company, acquired a third of the equity in Entrepo. BSR finalized the R&D on the wafer drive which it also manufactured. The BSR drive was used in the Rototronics Wafadrive.
Products
| Name | Description | Computers |
|---|---|---|
| A&J Micro Drive | Low cost, high-speed mass storage system that uses on “wafers” (endless loop tapes). Data transfer rate is many times faster than cassette and more reliable. Loads a 28k program in 24 seconds. Micro drive controller attaches to the expansion connector on the back and peripherals attach behind it. Most programs will run with little or | Timex/Sinclair 1000 |
| A&J Micro Drive Model 2000 | The TS2068 version of the A&J Micro Drive has all the features of the original and includes a Centronics printer interface. | Timex/Sinclair 2068, Downloadable |
| ESF Drive 2 | Supplemental Exatron Stringy Floppy drive. | Timex/Sinclair 1000, Timex/Sinclair 2068 |
| ESF/81 Monitor Program | The ESF/81 monitor program will allow you to program your Sinclair ZX81 at the most elementary level, in “machine language.” In. addition, the ESF/81 monitor will let you back up other machine-language programs stored on ESF wafers for extra security. | Timex/Sinclair 1000 |
| Microwafer | Continuous loop tape (“stringy floppy“) for the A & J Microdrive. | Timex/Sinclair 1000, Timex/Sinclair 2068 |
Books
Periodicals
Documents
| Title | Description | Computers |
|---|---|---|
| A & J Notes | Timex/Sinclair 1000 | |
| A&J Micro Drive Manual 1.0 Addendum | WHAT LENGTH IS MY TAPE? Underneath the “0” in Entrepo you will find a small number indicating the tape lenght. CAN I SAVE MORE THAN 9 FILES? Yes. If you look at page 241 of the Timex 2068 Personal Color Computer User Manual you will find a list of the character set. The next character | Timex/Sinclair 2068 |
| A&J Microdrive Model 2000 instructions from Knighted Computers | This letter contains some additional information that will spare you some quess work and its frustrations. So please, read the manual which came with the unit and this letter carefully, before using the Model 2000. | Timex/Sinclair 2068 |
| A&J Microdrive Schematics | Technical circuit schematic for A&J Microdrive Schematics. | Timex/Sinclair 1000 |
| A&J Model 2000 flyer | Marketing flyer from A&J Micro Drive describing products for Timex/Sinclair computers. | Timex/Sinclair 2068 |
| A&J Printer Interface instructions | In this package you will find all of the necessary items needed to make use of the printer port on the A & J Model 2000 Stringy Floppy Interface with Centronics compatible printers. | Timex/Sinclair 2068 |
| A&J Stringy Floppy dealer packet | Dealer packet for the A&J Stringy Floppy including the Model 1000 and Model 2000 price lists, dealer discount schedules, product specifications, order forms, and a letter from owners Jim and Annette Yowell announcing hardware and pricing updates. | Timex/Sinclair 1000, Timex/Sinclair 2068 |
| A&J Stringy Floppy for ZX81 TS1000 | User documentation for the A&J Stringy Floppy for the ZX81/TS-1000 and TS-1500, covering connection, operation using the Exatron operating system menu, storage specifications for Micro Wafers, and warranty information. | Timex/Sinclair 1000 |
| ESF/81 Monitor Program manual | Operating manual for the ESF/81 Monitor Program by A&J Micro Drive, covering installation, operation, and programming. | |
| Exatron Stringy Floppy Brochure | Product brochure from A&J Micro Drive for Timex/Sinclair computers. | Timex/Sinclair 2068 |
| Exatron Stringy Floppy ROM Disassembly | Z80 assembly language disassembly of the exatron stringy floppy rom ROM or program. | Timex/Sinclair 2068 |
| How to Convert Tasword II to the 2068 Microdrive | Step-by-step instructions by Eben Brown of E. Arthur Brown Company for patching Tasword II word processor to save and load to the A&J Microdrive on the TS-2068, including specific BASIC line modifications. | Timex/Sinclair 2068 |
| How to Run Pro:File 2068 on the A&J Microdrive | Instructions for running Pro/File 2068 from the A&J Microdrive (Mikrodrive) on the TS-2068, including the transfer procedure and selecting the correct interface type during setup. | Timex/Sinclair 2068 |
| Making 2068 Back-ups on the A&J Microdrive | Article explaining a convenient method for making backup copies of Pro/File 2068 data files on the A&J Mikrodrive, describing the file transfer procedure between wafers. | Timex/Sinclair 2068 |
| Stringy Floppy for Timex/Sinclair | Overview of the A&J Stringy Floppy system for Timex/Sinclair computers including the full collection of A&J documentation: the Model 1000 user manual, Model 2000 product sheet, price lists, and dealer packet. | Timex/Sinclair 1000 |
| Updates for Model 2000 Micro Drive | Microwafers: The Microwafer used in this Model 2000 Micro Drive is the Version II type wafer. When ordering additional microwafers, please use the following part numbers for the wafers of your choice: The amount of data storage per microwafer will vary with tape drive speed and number of files. Microwafer Write-protection The version II microwafer | Timex/Sinclair 2068 |
| User's Manual for the A&J Printer Interface | Operating manual for the User’s Manual for the A&J Printer Interface by A&J Micro Drive, covering installation, operation, and programming. | Timex/Sinclair 2068 |
| User's Manual for the Model 2000 Stringy Floppy | Operating manual for the User’s Manual for the Model 2000 Stringy Floppy by A&J Micro Drive, covering installation, operation, and programming. | Timex/Sinclair 2068 |
Downloads
| Name | Description | Computers |
|---|---|---|
| Micro-Wafer Test Program | Tests and reports on capacity and errors in A & J Micro Drive wafers. | Timex/Sinclair 2068 |
Articles
| Title | Description | Computers |
|---|---|---|
| A & J Microdrive Review | Its been out for three months now, its easy to use, and its fast! The A & J Microdrive has been a long awaited peripheral which is the best thing to come along since the 2068 itself! | Timex/Sinclair 2068 |
| A TS1500 A&J Microdrive Problem and Solution | Timex/Sinclair 1500 | |
| A&J Micro Drive System | Subroutine to create a command line and execute it from within a running program. | Timex/Sinclair 2068 |
| A&J Microdrive 2000 | Timex/Sinclair 2068 | |
| A&J Notes | When using the A&J Microdrive “ESOS” (Exatron Stringy Operating System), there are times when you don’t want it to change your RAMTOP. | Timex/Sinclair 1000 |
| Across the Pond | Updated version of MSCRIPT; now returns to BASIC for file save/load. Feature added by Zebra. Greeting Card Designer from Zebra. ZPRINT-80, also from Zebra, supports Aerco, both Tasman, and A&J interfaces with LPRINT, LLIST, COPY. | Sinclair ZX81, Timex/Sinclair 1000, Timex/Sinclair 2068 |
| Adapting Your Programs for the A&J Microdrive | Timex/Sinclair 2068 | |
| Alpha Strings$ | Correction to A&J article in n14; RAM chips from Jameco; adjustments to WORM program; Callisto Software’s ZX Hi-Res. | Timex/Sinclair 1000, Timex/Sinclair 2068 |
| Catalog Your A&J Wafers | Timex/Sinclair 2068, Type-in program | |
| Enhancing the A&J Microdrive | Programs to make working with the A&J Microdrive easier. | Timex/Sinclair 2068, Type-in program |
| Items Gleamed from Other Club Newsletters | The Plotter reports that most repairs sent to Dan Elliot are completed and returned quickly. Only those requiring SCLDs take longer. CATS has article about connecting QL to RGB monitor. L.I.S.T. reports A&J Micro no longer supplying microdrives because they cannot obtain tapes. | |
| Letters | Micro-Prolog Dear Sir, Reference the question in your last magazine about the availability of the program “Prologue” for the ZX Spectrum computer. Sinclair Research commissioned a version of the Prolog language for the Spectrum and sold it for about 30 Brit. pounds. However, when the rights to the Spectrum were transferred to Amstrad, all production | Timex/Sinclair 2068, Type-in program |
| Making 2068 Back-Ups on the A&J Microdrive | Technique for backing software from tape to A&J Microdrive. | Timex/Sinclair 2068 |
| Mass Storage for the TS-2068 | List of mass storage options, including: ZX-Microdrive, A&J Microdrive, DAMCO/Rotronics Wafadrive, AERCO 2068 disk system and RAMEX Millenia K interface. | Timex/Sinclair 2068 |
| New Products and Services (Syntax v5 n2) | New products from Pheonix Enterprises, D. Lipinski Software, Robert Fingerle, A&J Microdrive, Maples Enterprises, Cottage Technology, JK Audio, Interface Design, Apropos Technology. | |
| News From the Dealers | Curry Computing; Budget Robotics & Computing; American Design Components; WMJ Data Systems; Novelsoft; Chia-chi Chao; T & C Services; Lemke Software Development; Logic Sales Ltd.; A&J Assembly; Larken Electronics. | Lambda 8300 |
| Notes, etc. | Quotes Jim Howell, owner of A&J Micro Drive, about the origin of the company. | |
| Special Report: Mass Storage Devices For The TS 2068 | Brief overview of A&J Microdrive, DAMCO/Rotronics Wafadrive, Millenia K Disk Interface, Aerco FD-68 Interface. | Timex/Sinclair 2068 |
| Stringy Floppy for the Timex 1500 | Review and overview of the A&J Micro Drive stringy floppy system. | Timex/Sinclair 1000, Timex/Sinclair 1500 |
| Tasword Two on Microwafer | How to migrate Tasword Two to A&J Stringy Floppy. | Timex/Sinclair 2068, Type-in program |
| The A&J Microdrive | Review and overview of the system. | Timex/Sinclair 2068 |
| TS1500 A&J Microdrive Problem and Solution | Technique for bypassing a SAVE/VERIFY problem brought about by the combination of a TS 1500, TS 1016 RAM and the A & J Microdrive. | Timex/Sinclair 1500 |
| Vendor Report | Timex-Sinclair “survivor buttons; update on A&J Microdrives and wafers. | |
| Verifying MScript 5T on A&J Microdrive | Timex/Sinclair 2068 |
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