Transient thermal testing becomes more and more important for discrete power transistors (BJTs), IGBTs and MOSFETs. While reaching proper power levels is relatively simple for the two latter, measuring BJTs is more challenging. Existing standards such as the JEDEC JESD51 and MIL-STD-750 give general guidelines on their transient measurements, i.e. powering and transient recording. However, the typical realization of the standard needs two high current power supplies with fast switching capabilities. Furthermore, BJTs operate as high frequency amplifiers in the circuit scheme needed for thermal testing, which may cause unwanted oscillations. This paper proposes an exact realization of the existing standards with a more cost effective instrumentation and better stability. Also a small add-on to the T3Ster line facilitating the standard measurements is presented in a case study.