About Us

Engineering Innovation

Newtons4th Ltd (abbreviated to N4L) was established in 1997 to design, manufacture and support innovative electronic test instrumentation to a world-wide market. Specialising in sophisticated test equipment, particularly related to phase measurement, our product portfolio includes Power Analyzers, Frequency Response Analyzers (gain/phase analyzers), Impedance Analyzers, Vector Voltmeters, Phase Meters, true RMS voltmeters, Selective Level Meters and Laboratory Power Amplifiers. The company was founded on the principle of using latest technology and sophisticated analysis techniques in order to provide our customers with accurate, easy to use instruments at a lower price than has been traditionally associated with these types of measurements. Flexibility in our products and an attitude to providing the solutions that our customers really want has allowed us to develop many innovative functions in our ever increasing product range. In early 2015, N4L relocated to a state of the art manufacturing facility situated close to Leicester City Centre, England. The new site covers over 2,040 m² (22,050 ft²) and features a purpose built “clean” manufacturing environment with environmental control.

Our name, Newtons4th

The name Newton (Sir Isaac) is synonymous with a thorough understanding of physical principles from observation of the real world. His well known 3 laws of motion are so simple and clear that they are easily learned and applied, yet they give us the tools to analyse the motion of very complex systems. The number 4 represents innovation, building on what is already established. Newtons4th – innovation based on established fundamental principles.


Newtons4th Ltd are ISO9001:2015 registered, the internationally recognised standard for the quality management of businesses. In recognition of the technical innovation and commercial success of the PPA series, N4L received the “Innovation 2010″ Queen’s award for enterprise.



Newtons4th Ltd’s Head office, including Design, Manufacture and International Sales is located in Leicester, UK.

N4L Factory HQ