Issue link: https://iconnect007.uberflip.com/i/1524164
58 PCB007 MAGAZINE I JULY 2024 need for switching. At this stage of its devel- opment, the machine was capable of identify- ing a lot of issues on assembled backplanes and became a very popular piece of test equipment with major contract electronics manufacturers. Analysing lots of test results, it became apparent that the machine, for which the pri- mary objective had been to detect faults intro- duced during the assembly process, was find- ing a disturbing number of faults attributable to the bare board—in some cases as many as 70% of the total—a good justification for the devel- opment of a bare-board tester. is was around 2019. Several challenges had to be addressed. It wasn't practical to use spring probes because of the deleterious effect of the spring on the signal, and RoBAT also wanted to main- tain the principle of multiple con- nections per insertion. Because the development machine was basically a version of the high-end system for testing assemblies, it would not be cost-competitive in the bare board industry. en came COVID, which restricted travel and effectively shut RoBAT off from their mar- ket. But isolation presented an opportunity for the innovators and lateral thinkers to consider what applications they could envision that cap- italised on the attributes of their own compact TDR unit. e outcome was a suite of eight new products, from a benchtop unit for test- ing small, high-speed bare boards and coupons to a series of SCARA-based machines, which included a fully automatic TDR tester for bare and assembled PCBs. I was curious to know what "SCARA" signi- fied. Nockton explained that it was an acronym for a particular type of industrial robot, "Selec- tive Compliance Articulated Robot Arm," referring to its ability to move freely and main- tain stiffness in three axes while being compli- ant in the final axis. In the context of RoBAT's bare board TDR tester, the robot takes the place of the substantial X-Y-Z-axis gantry that is fea- tured in their mainstream equipment. Func- tionally, the SCARA machine used RoBAT's "mini test fixture" tools, with modules custom- ised in pitch and style of a high-speed connec- tor to correspond with the work being tested. Tool changing is automatic, and the system is capable of a full range of TDR tests and mea- surements. Importantly, the adoption of the SCARA principle substantially reduces the manufacturing cost and enabled this new equip- ment to be offered at prices that make it attractive to bare board manufacturers. When Nockton showed me around the Macclesfield facil- ity, I was amazed at the extent of capability and self-sufficiency that exists under one roof. All the way from design to finished product, the knowledge, the skills, and the equipment are there. New developments are evolving. It's a really nice set-up, and the sort of environment I would enjoy working in. I thanked Nockton most sincerely for mak- ing me welcome and for being so generous with his time and explanations. He tolerated my ramblings and reminiscences as we swapped anecdotes, realised how many people we both knew, and agreed what a small world it is in the electrical testing business. I set off to drive home in the rain, reflecting on a most interesting and informative couple of hours. PCB007 • RoBAT Leading Edge Signal Integrity Test Products • Pushing the Limits of PCB Impedance Control Pete Starkey is a technical editor for I-Connect007. New developments are evolving.