Your location produces terrain effect on antenna performance. With a bit of planning or luck, you can take on the “big guns”.

Recently, I have been exploring nearby terrain effect on antenna performance for my high frequency beam. This effect is particularly favorable on signals towards Europe from my location in Calgary.

My ham station is quite modest, with a small two element beam antenna on a fifty foot tower. But my hillside location next to a provincial park provides me with improved performance in certain directions. I thought I would do a comparison against our local “big gun” club station using High Frequency Terrain Assessment.

Our local “big gun” is VE6AO, the club station operated by the Calgary Amateur Radio Association. VE6AO is located a few miles to the north-east of me, next to Calgary’s airport. VE6AO operates with stacked four element beams at 30, 60 and 90 feet on a tall tower. It’s a really impressive set-up, built over many years by dedicated club members. The antenna at VE6AO would totally blow me away if not for one thing: the terrain effect on antenna performance.

The club station is located on relatively flat terrain. I am not.

Terrain Effect on Antenna Performance – My Station versus the Big Gun

The diagram above, produced with HFTA, shows three antenna performance curves at 14.2 MHz:

• The huge stacked array of VE6AO in red.
• My small two element antenna on my local terrain in blue.
• A hypothetical of my two element antenna’s performance if my local terrain were flat, in green.

If you compare the red and green curves, you can see that the big antennas at the club station would have a significant advantage over my set-up at all takeoff angles of use for communicating with Europe. Fortunately, the green line is hypothetical. I am not on flat ground. The blue line shows the terrain effect on antenna performance makes my small station very competitive with the “big gun.” For most low angles of arrival, my set-up comes very close in performance, within a few dB of gain.

I intuitively knew that I would get some benefit from terrain when I moved to this location. Until now, I never knew how much!

Now to be fair, I should mention that VE6AO has two stacked array towers that they can phase together, as well as much higher power, so they can out-gun me every time. Also, I just realized that the top antenna on the VE6AO stack is 100 feet, not 90 feet, but that would not make much difference to the analysis above.

You can evaluate your own terrain effect on antenna performance with the High Frequency Terrain Assessment software that comes with the ARRL Antenna Book by obtaining your specific terrain data from K6TU or elsewhere.