The Texas Instruments TI 99/4a computer. This system is attached to a Magnavox Professional display.
A nicely provisioned TI 99/4a with Peripheral Expansion System (model PHP 1200). The PHP1200 could accept a number controller cards including a disk controller, RAM, serial and parallel ports, etc. The system pictured above is configured with three drives, serial card for modem communications, and an extra 32K RAM. An insulated cable connects the back of the PHP1200 to a side cart part connector. Click image for larger view.
The beige version of the TI 99/4a. This version is functionally similar to the original silver 99/4a. Click image for larger view.
Diskette storage was cumbersome. Although third-party options eventually became available, Texas Instruments sold a Disk Manager cartridge and Peripheral Expansion Interface (model PHP1200) in order to provide disk drive storage functionality. Click image for larger view including drives and PHP 1200 unit view.