This study investigated the effect of training in equipment use on science teachers’ Pedagogical Content Knowledge (PCK) about the wave concept. The levels of teachers' reported PCK was explored before and after in-service training through interviews and Content Representations (CoRe). Furthermore, the study extended to investigating how the teachers enacted PCK when teaching the wave concept in their classrooms after the training. This qualitative research followed a case study method with three Grade 10 Physical Sciences teachers who were selected purposefully and pragmatically. Their pedagogical reasoning was elicited through a Video Stimulated Recall (VSR) interview and their general views about the training were obtained through a post-training interview. The framework was adapted from the Refined Consensus Model (RCM) and considered PCK at a topic and concept level, with each realm of PCK being underpinned by the Topic-Specific Pedagogical Content Knowledge (TSPCK) components, namely, the learners’ prior knowledge, the curricular saliency, representations, what is difficult and/or easy to teach and understand, and the conceptual teaching strategies. However, all five TSPCK components were considered. The study was centred on three key ideas in the topic of waves, namely: wavelength; frequency; and superposition. The participants' reported PCK improved and the footprint of the training was visible in the enacted PCK of all of the participants. This study suggests that training on the use of equipment improves teachers’ enacted PCK and this may ultimately lead to improved learner performance.