CW The 1st Digital Mode

Radio Frequency Interference (RFI)

As urban populations increase, there is an increase of radio interference (RFI) in the HF bands. This might be caused by powerlines and transformers, but it often comes from the hundreds of electronic devices like LED lights, inverters, cheap phone chargers, and garage door openers.

If you normally operate in urban centres, then operate with POTA, SOTA, or even in a Yukon campground, you might think your transceiver is not working because the receiver is so quiet.

When the power goes out in an urban area and you operate on battery power, you might be amazed to find how many signals had been hidden in the RFI. See three pictures below, showing the screen on an IC-7300 - the first two when there was a power outage, and third when the power came back on. Click on pictures for a larger image.

Back to HF Propagation