LRS member Brian Howie GM4DIJ gave an introduction to antenna modelling at the LRS meeting on 11 March 2015. This time he talked more specifically about "Optimization of Antenna Height Over Real Terrain in the Low VHF Bands" at the meeting on 22nd November 2017.
Brian writes: "It is common intuition that the higher an antenna is above the ground, the better it performs. Whilst this is true in most cases, the performance of an antenna a few wavelengths above ground is a complex interaction of the beam patterns and the local topography. It can be shown that in some cases a lower antenna can outperform one much higher.
I've been looking in particular at the local terrain at our contest site at Gatehouse of Fleet using an ARRL- supplied program HFTA, designed primarily for the HF Bands, to explore terrain effects on antenna performance at low VHF". Click for Powerpoint.