A Tier-1 aerospace and defense company came to Ball Systems with a need: flight-line technicians needed to connect a digital multimeter (DMM) computer directly to an aircraft engine's diagnostic port to pull live fault codes in the field. Off-the-shelf cabling wasn't going to cut it. This needed to be built to print, to spec, and to last.

The result was a rugged, precision interface cable assembly with a 28-pin bus terminal connector on one end and a 25-position D-sub connector on the other, built to customer print.

On one end sits a keyed, gold-plated D-sub connector; on the other, a circular MIL-spec connector, joined by shielded, high-flex signal wire engineered to survive the vibration, temperature swings, and EMI-heavy environment of a flight line or maintenance hangar. Every assembly is built and tested against the customer's Acceptance Test Procedure, with data communication and continuity validated against flight and flight-simulated results before it ever leaves our facility.

And this wasn't a one-and-done build. The program has come back for repeat production runs, which, in this business, is the real review that matters. It means the OEM trusts Ball Systems to reproduce exact fit, form, and function order after order, without drama.

What Actually Goes Into a Cable Like This

It's easy to think of a cable assembly as a commodity — wire, connectors, done. In practice, every custom cable that leaves Ball Systems goes through the same disciplined process, regardless of customer or industry:

• A build-to-print engineering review against the customer's drawings, 3D models, and specifications
• Sourcing of mil-spec and commercial-grade components — D-sub and circular connectors, multi-conductor and shielded cable, high-temperature wire insulation — with full pedigree back to the OEM or an authorized franchised source
• Hand-built termination, potting, and strain relief, including RTV silicone sealant and heat-shrink insulation, for long-term environmental durability
• 100% visual and mechanical inspection — scratch-free finish, correct mechanical details, weld and joint integrity — signed off before anything ships
• Individually serialized, laser- or thermal-transfer labeled assemblies for full lot traceability

That last point sounds small until you need it. A serial number on a label is what lets us trace a specific cable back to its exact build record years later — which components, which lot, which technician signed off on it. It's a small detail that makes a big difference the day someone needs an answer fast.

What Actually Goes Into a Cable Like This

It's easy to think of a cable assembly as a commodity — wire, connectors, done. In practice, every custom cable that leaves Ball Systems goes through the same disciplined process, regardless of customer or industry:

• A build-to-print engineering review against the customer's drawings, 3D models, and specifications
• Sourcing of mil-spec and commercial-grade components — D-sub and circular connectors, multi-conductor and shielded cable, high-temperature wire insulation — with full pedigree back to the OEM or an authorized franchised source
• Hand-built termination, potting, and strain relief, including RTV silicone sealant and heat-shrink insulation, for long-term environmental durability
• 100% visual and mechanical inspection — scratch-free finish, correct mechanical details, weld and joint integrity — signed off before anything ships
• Individually serialized, laser- or thermal-transfer labeled assemblies for full lot traceability

That last point sounds small until you need it. A serial number on a label is what lets us trace a specific cable back to its exact build record years later — which components, which lot, which technician signed off on it. It's a small detail that makes a big difference the day someone needs an answer fast.

An HHDLU Interface Cable

This companion build-to-print cable assembly is labeled for an HHDLU-to-55FDB/55HFDB interface. It pairs a 28-pin bus terminal connector on one end with a 25-position D-sub connector — a punch-contact receptacle, complete with matching spring latch and backshell — on the other, joined by 13-pair, 28 AWG cable.

Every termination is wrapped in Kapton insulating tape, sealed with RTV silicone adhesive, and protected with heat-shrink insulation at the strain relief, then finished with a permanent, individually printed cable label for full lot traceability before it ships. It's built to a standard 4-week lead time, quoted and tracked through our standard build-to-print process.