Field strength measurements are made to study the Single knife edge diffraction propagation in the hilly terrain of Tirupati, Southern India. TV signals originating from Narayana Giri Hill in VHF band are monitored at 4 different locations of Tirupati for this purpose. The observed values are converted into path loss values and are compared with prediction techniques. An attempt is made to study the adaptability of these techniques and found that ITU-R, Epstein – Peterson, Deygout and Edward – Durkins methods are in closer agreement with the observed path loss where as Blomquist – Ladell over estimates the observed path loss.