We measure the transmission secondary electron yield of nanometer-thick Al 2 O 3 /TiN/Al 2 O 3 films using a prototype version of a Timed Photon Counter (TiPC). We discuss the method to measure the yield extensively. The yield is then measured as a function of landing energy between 1.2 and 1.8 keV and found to be in the range of 0.1 (1.2 keV) to 0.9 (1.8 keV). These results are in agreement to data obtained by a different, independent method. We therefore conclude that the prototype TiPC is able to characterise the thin films in terms of transmission secondary electron yield. Additionally, observed features which are unrelated to the yield determination are interpreted. K: Electron multipliers (vacuum); Photon detectors for UV, visible and IR photons (vacuum) (photomultipliers, HPDs, others); Timing detectors; Dynodes and Tynodes 1Corresponding author.