[Paul] used a 4″ (10 cm) clamp; that which looks fine for a wide ... onto Technic pegs go into the holes on the beam to hold the PCB edges firmly, while the swiveling action adapts to odd ...

Building the assembly into a rudimentary enclosure made from sawn-up raw copper clad board, with the pogos facing upwards, and a simple clamp on top, allowed the PCB-under-test (let’s call it ...