The knowledge of signal demodulation processes using superheterodyne receivers is of
great importance in the field of telecommunications. Superheterodyne receivers receive the current
focus of many scientists in a wide variety of applications. This topic is part of the syllabus of the
Communication Theory course at the School of Telecommunications of the Polytechnic University
of Cartagena, Spain. The authors found that the academic performance of the students had not
been entirely satisfactory in recent years. This situation was aggravated during the COVID-19
lockdown. Students had to reinforce their knowledge independently at home, despite the support
provided by teachers. To the best of the authors’ knowledge, there is a noticeable lack of educational
tools in this area; of those that are available, they exhibit a mismatch with the specific needs of
this subject. This manuscript shows how the design of the educational software tool DOSHER,
tailored to enhance the understanding of superheterodyne receivers, successfully alleviated the
aforementioned drawbacks. DOSHER was designed, developed, and applied during the 2020–2021
academic year (during the COVID-19 lockdown). The results show that students were not only
very satisfied with its use, but they also improved their marks. Analysis of students’ academic
performance in the year of DOSHER implementation showed an average improvement in their
marks of between 9–12% compared with previous years. In 2021–2022, when DOSHER was fully
operational from the start, the improvement in terms of pass rate (31%) at the first mid-term was
significant compared to previous years (<20%).
