EIS 15510 T1 Interface Card Rev B 15514 15513 Telecom ISA Bus Board

EIS 15510 T1 Interface Card Rev B 15514 15513 Telecom ISA Bus Board

The EIS 15510 is a T1 interface card designed to provide a physical and logical interface between host systems and T1 digital telecommunications lines. Referenced by related board numbers 15514 and 15513, this Rev B card is a full-size ISA bus expansion board populated with a dense array of logic ICs, a main controller chip, and supporting circuitry. A DB-15 connector is present on the card edge, and an internal ribbon cable header is visible on the board. These types of T1 interface cards were used to connect computing systems directly to T1 (1.544 Mbps) digital carrier lines for voice, data, or multiplexed traffic.

Specifications & What's Included

• Part Number: 15510 (also referenced as 15514 / 15513)
• Hardware Revision: Rev B
• Interface: T1 digital telecommunications
• Bus Interface: ISA (full-size card)
• On-board connector: DB-15 on card edge bracket
• Internal header: ribbon cable connector (visible on board)
• DIP switches present for configuration
• Dense IC population including main controller and logic array chips
• Board only — no cables or accessories included

Applications

T1 interface cards like the EIS 15510 were used in the 1980s and 1990s to connect ISA-bus host computers and telecommunications systems directly to T1 digital carrier circuits — the 1.544 Mbps North American standard for digital telephony and WAN data transport. These cards handled the framing, line coding (typically AMI or B8ZS), and synchronization required for T1 connectivity, and were deployed in applications such as PBX systems, call-center platforms, data multiplexers, and early voice-over-data systems. The ISA bus form factor places this card in the era of mid-to-late-1980s through mid-1990s computing hardware. Today, boards like this are primarily sought for maintenance and repair of legacy telecommunications equipment and systems that still operate on original hardware.