On 6/25/2026 12:24 AM, John Randall via Topband wrote:
I dont say much on this form, but this squibble awoke something in me. Most of you guys on top band have massive land, plots whatever, so can erect huge antennas by comparison, perhaps now you know how most of us less fortunate have to cope with 20ft by 20ft back yard for our antennas.
I can relate, John. Most of my 70 years as a ham was spent in towns and cities on small lots and with little money. I had pretty good used radios, but limited antennas. From my city lot in Chicago, it was a struggle to work the west coast of the US, and I worked no DX at all. Serving as the representative of the Pacific Division on ARRL's Contest Advisory Council, I work hard to represent hams like you.
That all changed 20 years ago, when I retired and moved to 8 acres in the Santa Cruz Mountains, where I have the station beyond my wildest dreams.
But I remember what those early 50 years were like. And I'm also an EE by training, and with a specialty in RFI. So I know what high power would do in a QTH like yours -- every piece of consumer equipment in your home and the homes of your neighbors would be turning flips when you transmitted, so you'd face a rebellion from your neighbors. AND, thanks to the dozens of noise sources in your home and the homes of each of those neighbors, all you would hear would be the biggest of the signals above their noise. And even here, noise levels have increased by 15-20 dB, depending on direction.
We can't "brute force" a solution to this. We've got to work smarter, taking advantage of new technologies that reject noise. There are digital modes that can average multiple transmissions of very limited data -- callsign, signal report, QTH -- to offer more than 30 dB of noise rejection. These are not "conversational" modes -- rather, they use the fundamentals of communications theory that I learned baby steps of in my senior EE courses in 1964, and that have grown exponentially in the decades since. Early variations of these techniques are how we talk to spacecraft launched 30 years ago to control them and download from their instrumentation.
WSJT-X, by Nobel-laureate Joe Taylor, K1JT and a team of programmers, combines a dozen or so digital modes for various forms of propagation. There's one for meteor scatter, where propagation exists in short bursts, for paths with lots of attenuation and fading, like topband. Others optimized for tropospheric propagation on VHF/UHF. FST4 is the one designed for propagation at LF and MF. FST4W is designed to replace WSPR, providing a few dB greater noise immunity. Noise immunity is increased by longer transmitting intervals and by averaging.
73, Jim K9YC _________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
