LGR Meets Radio Shack’s 1983 Hard Drive, Twelve Megabytes and a Rusty Jet Engine

Radio Shack asked $3,495 in 1983 for a 12-megabyte external Winchester meant to sit beside a TRS-80 Model II, Model 12, or Model 16. That price lands near $11,754 in 2026 money. Clint Basinger of LGR pulled one of those units from long-term storage, cracked the case, and gave it a brief power-on test before packing the vintage hard drive off to a museum.

Catalog No. 26-4152 Having identified the primary drive, a matching secondary unit with Catalog number 26-4153 was available for a stunning $2,495 back then. However, if you wanted the installation done, you would have to pay extra. Back then, the only way to load software into your home computer was to utilize 8-inch or 5.25-inch floppies, or a cassette tape. A sealed 12-million-character disk, on the other hand, was a genuine beast in an office that ran payroll, inventories, and customer records around the clock.

Inside the metal cabinet, there is a Tandon TM-603, a full-height 5.25-inch drive with three platters and six recording surfaces. Six heads share one actuator, allowing a single seek to easily strike a six-track cylinder. The platter is spinning at 3,600 rpm. You’re talking about 8.3 milliseconds of rotational delay time. Data leaves the heads at a scorching five megabits per second. Radio Shack advertised formatted capacity as 11.6 megabytes on the first device and 12 megabytes on each add-on drive they sold. They claimed that track-to-track seek times were as short as 3 milliseconds. It measures 5.5 by 14 by 15 inches and comes equipped with its own power supply.

A different controller card exists within the same box. At the heart of it is a 1976 Signetics 8X300 chip, which functions as a microcontroller and allows the Tandon drive to fool the TRS-80 into believing it is a Western Digital. A large ribbon cable extends from the back of the enclosure and connects to a corresponding host card within the computer. Clint discovered that the interior still looked factory-new after more than 40 years. There was an error map label, a serial number, and a few factory bodges left, but the rifa filter capacitors in the power supply forced him to shorten the test.

He flipped the front panel switch, and the motor produced a lengthy grinding whine that sounded like to a rusty jet engine or a table saw resuming operation after years of inactivity. The bearings were slightly noisy, but the platters were not locked down. He shut off the power after only a few seconds. It’s made entirely of metal, with a keyless power switch, and two status lights that give it a vintage industrial aspect; Clint described it as “Star Wars-esque.” A label indicating that opening the case would void the warranty.

Clint is donating the drive to the Midwest Computer Museum, and he intends to drop it off at VCF Midwest in 2026, along with a plethora of other vintage computer detritus. The museum staff has the TRS-80 machines functioning wonderfully, so there’s a decent possibility this ancient Winchester will spin up for the guests. Business software in 1983 thought 12 megabytes was plenty for databases and even multi-user Xenix sessions on the Model 16. Only a few individuals outside of professional shops had ever seen a disk this large on a microcomputer that year, unless you count the luxury IBM PC/XTs with a 10-megabyte drive. 43 years later, the Radio Shack box still appears to be waiting for someone to come along and repair it with a new host and filter caps.
[Source]