Description
DTC 7287 16-Bit ISA RLL Hard Disk Controller Card 1:1 Interleave XT/AT
The DTC 7287 is a full-length 16-bit ISA hard disk controller card designed for IBM AT-class and compatible desktop PCs. It uses RLL (Run Length Limited) encoding with a 1:1 interleave ratio, allowing the drive heads to read every sector on each disk revolution without waiting for the disk to rotate — delivering faster sustained throughput than MFM controllers of the era. The card supports bus speeds up to 16 MHz and fits any standard 16-bit ISA slot.
Specifications & What's Included
- Manufacturer: DTC (Distributed Technology Corporation)
- Model: 7287
- Secondary Part Number: PAR83A (visible on main controller chip)
- Hardware Revision: REV. 4
- Bus Interface: 16-bit ISA (AT-bus)
- Encoding: RLL (Run Length Limited)
- Interleave: 1:1
- Bus Speed: Up to 16 MHz
- Form Factor: Full-length ISA card
- Drive interface headers visible on PCB (for RLL-encoded hard drives)
- Logic ICs visible on PCB: SN7410N, SN7416H (Texas Instruments); MS3236P; NEC Japan IC; CRN15A
- ISA bracket included (metal, full-height)
- Card only — no cables included
Applications
The DTC 7287 was designed for late-1980s IBM AT-compatible desktop computers — the generation of 286 and early 386 systems that used the 16-bit ISA (AT) bus for storage expansion. RLL controllers were developed as a higher-density alternative to MFM controllers, storing roughly 50% more data on the same MFM-certified drive platters by using a more efficient encoding scheme. At 1:1 interleave, the DTC 7287 eliminated the rotational latency penalty common on earlier MFM controllers that required 2:1 or 3:1 interleave settings to keep pace with slower CPUs. These cards were a popular performance upgrade in their era, pairing with ST-412/ST-506 interface hard drives in desktop towers and desktop workstations. Today they are sought by vintage PC collectors, retrocomputing enthusiasts, and technicians restoring period-correct 286/386-era machines. Compatible systems include IBM AT, IBM PC/XT/286, and a wide range of compatible clones with 16-bit ISA slots.
This DTC 7287 16-bit ISA RLL Hard Disk Controller Card has been inspected and appears to be in good used condition. The PCB is clean with no visible cracked traces, burn marks, or broken components. Normal handling wear and light oxidation on the ISA edge connector are consistent with its age. The card was pulled from a working PC environment but has not been powered up or tested at our facility. Please review all photos carefully and contact us with any questions before purchasing.
Warranty Information
Additional Information
Brand: |
DTC |
Model: |
7287 |
MPN: |
7287 |
Secondary Model: |
PAR83A |
Type: |
RLL Hard Disk Controller Card |
SKU: |
10250 |
Bus Interface: |
16-Bit ISA (AT) |
Encoding Standard: |
RLL (Run Length Limited) |
Interleave: |
1:1 |
Bus Speed: |
Up to 16 MHz |
Form Factor: |
Full-Length ISA Card |
Compatible With: |
IBM AT and compatible PCs with 16-bit ISA slot |
Interface: |
ISA 16-bit |
Country/Region of Manufacture: |
United States |
Seller Notes: |
Card only, no cables included. Inspected and in good cosmetic condition. |
Condition Notes: |
This DTC 7287 16-bit ISA RLL Controller Card has been inspected and is in good used condition. PCB is clean with no visible damage. Pulled from a working environment; not tested at our facility. |
California Prop 65 Warning: |
WARNING: This product can expose you to chemicals including lead and lead compounds, and DEHP (a phthalate), which are known to the State of California to cause cancer and birth defects or other reproductive harm. Go to P65Warnings.ca.gov |
