The Propagation Beacon
This is a quick update regarding a newer project I have engaged over the past month or so: a Propagation Beacon. I have been fascinated with these beacons on ten meters for some years now. The purpose of this program is to provide a "boots on the ground" source to determine propagation on ten meters, and, by extrapolation, the state of the Maximum Usable Frequency (MUF) on HF, ten meters being the highest portion HF region. In other words the Maximum HF Frequency Band. Beacons are typically very low power devices, ranging anywhere from 100 mW to 20 watts. Most of them are about five watts. The antennas are (or should be) omni-directional unless aiming at a specific direction for a specific utilization.
The idea: if I can copy a five watt signal from 2000 miles away emanating from a simple antenna of no great height, the band must be propagating well. We can safely assume the MUF is at least reaching the beacon's frequency.
While many profess to use the FT8 frequencies as a "tell tail" for MUF, that can be very misleading. While it is true there are 100 watt beacons on ten meters, I can count them on one hand. The IARU discourages that level of power, it defeats the purpose of the Propagation Beacon! FT8 stations are all over the place with power, high gain antenna systems, etc. One cannot accurately ascertain the level of propagation, not with any degree of certainty. I know. I do FT8 myself, and I know what some of these stations are running. One I know runs a full kilowatt on a yagi system up over 70 feet in elevation. One visit to QRZ.com, looking over the photos and station description reveals these stations run very high gain systems. They approach FT8 like a contester, and honestly so: that is how FT8 is set up. It wasn't meant to be that way originally but it is what it has become.
Ergo, FT8 does not replace the classic low power propagation beacon when it comes to propagation assessment.
Registered vs Unregistered
There are two types of these beacons: the Registered Beacon and the Unregistered Beacon (often referred to by the beacon community as a "rogue" beacon.) Let me comment on this:
The Beacon Program is just that, a program. As such, there needs to be something of an organized approach. At this point the primary organizer is the International Amateur Radio Union (IARU), in cooperation with the ARRL, which has an appointed representative and contact person for each region. This person establishes your registration and "assigns" a frequency, which is based on a coordinated schedule. Coordination is necessary so as to not cause unnecessary QRM to other beacons or services worldwide. This is owing to the international propagation possible on Ten Meters.
"Beacon Protocol"
What I call "Beacon Protocol" is actually quite simple, and technically not official. Stations are requested to be frequency stable, not to exceed 20 watts. The ten meter "beacon sub-band" in Region 2 ranges from 28.2 to 28.3 MHz, limiting emissions to data or CW. Suggested antennas are omnidirectional in orientation, and what I would call average residential, mast mounted height. (mine is a half wave "Ringo" at 20 feet, bolted to the gable end of my house.)
Beacons are not meant to be DX machines, they are meant to provide data sufficient to fairly assess propagation conditions. Universally, Beacons offer a constant rotation CW transmission indicating the beacon call, beacon suffix (/b or bcn), location and/ or grid square. CW is typically the primary emission, however data signals are also permissible. What is sent on each rotation can differ from beacon to beacon. Some even offer email addresses for reporting reception. Beacon monitoring has become something of an SWL interest, you can find articles posted online, dedicated entirely to beacon monitoring.
On the other-hand there is the unregistered beacon. Essentially someone gets a beacon going, and parks it wherever so desired, typically with minimum regard to any established band organization. "Rogue" beacons are not illegal per se.... but are usually not coordinated with the beacon community which means that there are risks of doubling signals and potential interference. All this to say: if you are inclined to become involved with the Beacon community, don't be a lone wolf. Please become involved constructively!
Our Rep for Region 2 is Jerry AC5JM. I linked his email, but if that link fails, copy and paste:
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Jerry's a great fella to work with, is responsive, and very helpful and encouraging. Do reach out to him.
The Function of WD4NKA/B
Currently, my beacon serves a twofold purpose. Primarily, it is a 3-5 watt propagation beacon. Secondarily, it transmits weather information for local consumption during local storm events. This weather retransmitted directly from our local Aviation Weather station at Orlando Sanford International Airport, Sanford Florida (KSFB). The transmission mode is PSK31. Jerry did some footwork for me and we determined that digital beacon transmission is legal. During these weather events the power is elevated to 20 watts. Those of us who entered ham radio from out of the CB ranks can remember how well a 5-watt base station on a half wave ground plane could cover an area on AM. Imagine what local coverage a 20 PSK signal has using the same antenna at the same height, 20 feet. WD4NKA/B can operate on independent D.C. sources.... just in case. (read: I keep a few car batteries under charge at all time.)
Currently, my Icom IC740 provides the PSK via FLdigi, but soon another HTX-100 will fill that role.
Of course, after storm weather events the beacon returns to it's normal cw ID rotation.
Beacon I.D. rotation
The current identification in rotation reads: "v v v v v v de wd4nka/b wd4nka/b deltona fl el98iv pwr 5w"
After 20 seconds there is a ten second tone (used to check the system) and the rotation recycles.
The antenna used for WD4NKA/B is a Cushcraft AR10 "Ringo", mounted at 20ft. Since the HTX-100 has a low-power input of 5 watts, the output is about 3.5 watts. By the time the antenna sees the signal at the input, it's more like 3 watts. Nonetheless, I report the power input to the final.
That's pretty much it for now. Listen out for WD4NKA/B on 28.299.5 MHz sometime. If you hear it, drop me a line at wd4nka@gmail.com . Let me know how it sounded, along with signal strength near as you can tell, and band conditions at time of copy. Date and time would be helpful as well. In time I hope to have a special QSL card to send back in acknowledgement.
That's all for now. I may edit this post as needed. This is a work in progress.
73, de wd4nka ar k
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