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In the beginning...My first Z80 machine (Osborne 1) atop my first 8080 machine (IMSAI 8080). Notice the custom fan and "Drive C" ramdisk on the Osborne. The IMSAI contains a custom ROM monitor I programmed and a custom S-100 card I designed and built - a 512K flash ram chip with a library of sample software from the period: BASIC, Life, Star Trek, editor, assembler, etc. Great box for demos! Download the Drive C software Download the IMSAI Monitor Program |
A desk full of AltairsClockwise from top left: Altair 680, contemporary LCD flatscreen, Single 8" drive, Altair 8800B, contemporary cassette recorder/player, Altair 8800 The 8800B has Extended BASIC in ROM and the 8800 has a custom ROM monitor I programmed, the original Micro-Soft 4K BASIC in ROM, a Cromemco Dazzler, and an ACR cassette interface. This unit runs with the ASR-33 shown below. Sample Dazzler output is on the right ----> Download the ACR Utilities Download the Altair 8800 Monitor Program |
The Southwest Technical Products deskClockwise from top left: AC-30 cassette interface, Superscope cassette unit, 6800 machine, 6809 machine, dual minifloppy (5.25") drives. The 6800 machine contains an EPROM burner and a math co-processor which is just an RPN calculator chip. Like having a giant HP calculator on your desk. |
The Heathkit H8 and ET3400The H8 was an 8080 machine with a nice monitor but non-standard bus. This one has 16K RAM, serial I/O and a cassette interface. The ET3400 was a 6800 based trainer with breadboarding area for experiments. This one has the expansion box underneath with more memory and Tiny Basic. |
The venerable Sol-20 by Processor Technology8080 CPU, 5x S-100 Slots, with integrated keyboard, video output, and cassette interface. And beautiful walnut sides. Micropolis produced an early 5.25 inch floppy kit for the S-100 bus. The kit included software too: The Micropolis Disk Operating system (MDOS), a BASIC interpeter, and an 8080 assembler. |
The Netronics Elf IIThis was my first computer. It uses the RCA 1802 processor with a hex keypad and LED display. This unit has the "Giant Board" for I/O, a whopping 4K of RAM, an EPROM burner, and an RPN BASIC in ROM. The ASCII keyboard pictured also has a video display card and RF modulator allowing connection to a TV set. The small box on the left is the power supply. See the Netronics Advertisment |
Osborne Executive SystemBusiness Computing 1980's style. The Osborne "Executive" was a refinement of the portable Osborne 01. It runs a Z80 @ 4Mhz with 124K RAM and a slightly larger screen. Also pictured is an aluminum bodied Hayes smartmodem, a Westwind external hard drive specifically made for the Osborne, a Vortrax speech synthesizer atop it, and a Diablo daisywheel printer on the far right. |
The Northstar HorizonAn early disk based system. All you needed was a termial - like the Televideo 920 pictured. The Horizon ran a 4Mhz Z80 with 64K RAM and dual 5.25 inch disk drives. It used the NSDOS operating system, or CP/M. This one has an external modem, and is pictured next to a Heathkit shortwave receiver set and a contemporary ASUS laptop. |
HP67 and the BlackBoxI've also done some calculator hacking in my day. This a Hewlett-Packard HP-67 calculator with a "BlackBox" I built to allow access to normally forbidden regions of memory. It also allows more control over the 7-segment LED display - useful for games. |
The Teletype model ASR-33This Teletype (TTY) was the standard terminal throughout the 60's and the early 70's, before CRT's became popular and affordable. ASR meant "automatic send and receive". Which means this model could read and write via punched paper tape. The little black box on top is a 20ma to RS232 converter and allows me to use the TTY with any computer with a serial port. And yes, I can even connect it to my PC and use it as a printer or to punch binary files to paper tape to share with my fellow old geezers. |
GODZILLAMy second IMSAI, this unit ran a BBS for many years before it's retirement. It has an upgraded Z80 CPU, 64K RAM, dual 8 inch floppy drives, and a 33Meg hard drive (which weighs 90 lbs!). The black laptop on top is used as a terminal. |
Contact: john_crane_59@yahoo.com (John Garza)
Last update: July 21, 2012