Ham radio signals strength and distance to furthest readable contact changes on a daily, in fact hourly basis. I have noticed that weather can have a huge impact on propagation both in the low bands and in the high bands. On the high bands, in a mobile (my best rig), it can be annoying. I have my memories set to local repeater frequencies as well as police, ambulance and airport frequencies. But when there is band enhancement due to weather conditions, I hear distant repeaters that are on the same frequency as local repeaters. They are quite weak and are annoying to the extent that you can barely hear the conversations and it prevents the scanner from hearing the rest of the action around town.
On HF, however, it is exactly the opposite. I have noticed that storms over certain areas can provide some really enhanced ham radio paths. For example, contacts to the west at noon tend to be rare for me. But when a storm is rolling through Montana, then the Montana contacts come booming in to my mobile!
I have done a bit of research to try and understand what is happening. I don’t want to become a scientist or electrical engineer. I just want to know why my rig seems to work so darn well at times and why at other times there seems to be nothing. Is this due to a bad ground or band conditions?
One nice resource is here: http://www.tpub.com/content/neets/14182/css/14182_97.htm . This site gives a really nice, not too technical, explanation of what is happening. It has a good write-up and has some nice drawings that make it easy to understand the write-ups. Another resource I use is on my very own site at http://www.hamradioresources.com/hamradio – just look for “DX Forecasts”. Also look for “HF Propagation Tutorial”. I check the DX Forecasts probably once a week. Sometimes I check it after an unexpected contact. I am amazed at how often I make a contact and then find that the forecast was for good propagation in that area.
I encourage you to pay attention to what weather patterns are present all the way between your distant (DX) contacts and you. Both on ham radio and shortwave radio. I think it will add some interest to your hobby.
Stay radio active!
Jon Kreski, AB9NN
Owner
http://www.HamRadioResources.com
