The scene
A discharge inside insulation may be smaller than the noise around it. The engineering problem is therefore not merely to detect a pulse, but to decide whether it is real, where it came from and whether another laboratory could measure it again. That problem brought together experience from Robinson, TETTEX, HAEFELY and HIPOTRONICS. They were separate instrument traditions before later documentation drew them into the history of the DDX family.
The engineering challenge
The devices trace a progression, not a single inventor’s eureka moment: TE 560/561, TETTEX 9120 and earlier Robinson systems belong to the analogue-to-digital transition; later DDX 7000/8003, 9121b and 9160/9161 instruments added filtering, channels and software-driven analysis. Historical diagrams disagree on some dates, and a new instrument, a revision and a software feature are not interchangeable milestones. The original manufacturer diagrams and brochures remain the cited evidence, not a definitive personnel register.
Why it matters
The engineers deserve equally careful attribution. Project-insider testimony associates Dr. Tomitohy with early Robinson work, recalls an earlier UK Robinson software team, and credits Bernhard Decamp with leading the TE 560/561 project; those memories have not been verified against independent staff records. Separately, named technical publications support later work by Petr Mráz, Patrick Treyer and Urs Hammer around the DDX 9121b generation. The story belongs to successive teams, not to a retrospectively invented list of sole inventors.
What the historical record shows
The older TE 560 hardware anchors the analogue branch; a product photo alone does not identify its complete design team.
This historical equipment photograph documents the physical layout of the TE 560, distinguishing the analogue hardware tradition from later software developments. The image, not just a model name, is the subject being compared.
Image citation · PD Line History (2 Nov 2020), slide 10 · HAEFELY technical-history presentation, original image rights-holder not specified
Contextual illustration from user-supplied historical presentation
Open original source
TE 571 documents the transition to digital analysis, a different engineering phase from the earlier UK software branch.
The control and display layout of the TE 571 illustrates the transition to digitally assisted PD interpretation; a photograph supports this comparison without assigning exclusive authorship.
Image citation · PD Line History (2 Nov 2020), slide 9 · HAEFELY technical-history presentation, original image rights-holder not specified
Contextual illustration from user-supplied historical presentation
Open original source
DDX hardware embodies the later convergence; individual software and hardware roles are recorded separately.
The visible later DDX instrument makes the change of instrument generation concrete; it does not prove which named engineer invented each subsystem.
Image citation · PD Line History (2 Nov 2020), slide 3 · HAEFELY technical-history presentation, original image rights-holder not specified
Contextual illustration from user-supplied historical presentation
Open original source
The 2017 brochure identifies the DDX 9121b as a multichannel digital PD detector. Its illustrated hardware does not establish the authorship of its software or individual engineering contributions.
A tightly framed product view is quoted to visually distinguish the DDX 9121b generation discussed in this story from the historical TE 560/571 instruments; the original brochure and page are linked.
Image citation · HAEFELY, Partial Discharge, manufacturer brochure dated 20 Sep 2017, page 10 · HAEFELY Hipotronics / TETTEX (manufacturer); individual photographer not credited
Documentary crop from manufacturer brochure (2017), page 10; cropped/resized; public rights review pending
Open original sourceSources, scope and limits.
Device chronology: manufacturer diagrams, brochures and named technical papers. Tomitohy, the earlier UK Robinson software team and Decamp: internally supplied oral testimony dated 12 November 2026; roles are credited as testimony, not independently certified employment or sole-inventor records.
- Haefely Hipotronics Partial Discharge corporate brochureS-015 · corporate_publication · indexed_text_and_diagram_description
- Original HAEFELY Hipotronics PD lineage brochure historical chartS-F2-020 · corporate_publication · original_pdf_search_extracted_chart
- HAEFELY TD-103 2015 Mráz Treyer Hammer Gonzalez PD analysisS-F2-021 · corporate_publication · original_authored_technical_paper
- HAEFELY TD-106 2017 Treyer Mráz Hammer cable PD site locationS-F2-022 · corporate_publication · original_authored_technical_paper
- HAEFELY TD-108 2019 guidelines PD measurement IEC 60270 Mráz Madhar Treyer HammerS-F2-023 · corporate_publication · original_authored_technical_paper
- HAEFELY TD-120 2025 Mráz Eckert Hammer time/frequency PD measurementS-F2-024 · corporate_publication · original_authored_technical_paper
- NETA World 2024 independent PD history: Robinson ERA, Tettex and Hipotronics evolutionS-F1-018 · third_party_analysis · industry_technical_history
New documentary references
- HAEFELY Partial Discharge manufacturer brochure: lineage and DDX 9121b timelineDates reflect retrospective catalogues, not an independently established sole inventor list.
- Internal PD Line History presentation, 2 November 2020Original attached project material with presentation/slide provenance, quoted products as historical evidence.
Visual quotations document individual historical points with named sources and creators; they are not a general image-library licence. Equipment claims are intentionally narrower than the surrounding institution’s activities.