--- service: "Publicasta" schema_version: "1.0" article_id: 844 title: "A 36.680 MHz FT8 Beacon Is Testing Autumn F2 Propagation: How to Listen, Log, and Interpret the Results" language: "en" default_language: "en" canonical_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment?lang=en" json_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment.json?lang=en" api_url: "https://publicasta.com/api/public/v1/channels/ham_radio_diy_electronics/articles/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment?lang=en" channel_url: "https://publicasta.com/api/public/v1/channels/ham_radio_diy_electronics" channel_articles: "https://publicasta.com/api/public/v1/channels/ham_radio_diy_electronics/articles" search_url: "https://publicasta.com/api/public/v1/search" documentation_url: "https://publicasta.com/api-docs#reading-publicasta" openapi_url: "https://publicasta.com/api-docs/openapi.json" published_at: "2026-10-09T14:39:29+00:00" updated_at: "2026-10-09T14:39:29+00:00" translations: - language: "ar" html_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment?lang=ar" markdown_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment.md?lang=ar" json_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment.json?lang=ar" - language: "de" html_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment?lang=de" markdown_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment.md?lang=de" json_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment.json?lang=de" - language: "en" html_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment?lang=en" markdown_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment.md?lang=en" json_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment.json?lang=en" - language: "es" html_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment?lang=es" markdown_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment.md?lang=es" json_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment.json?lang=es" - language: "fr" html_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment?lang=fr" markdown_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment.md?lang=fr" json_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment.json?lang=fr" - language: "pl" html_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment?lang=pl" markdown_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment.md?lang=pl" json_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment.json?lang=pl" - language: "ru" html_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment?lang=ru" markdown_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment.md?lang=ru" json_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment.json?lang=ru" - language: "zh" html_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment?lang=zh" markdown_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment.md?lang=zh" json_url: "https://publicasta.com/ham_radio_diy_electronics/ly2yr_36mhz_ft8_beacon_autumn_receive_experiment.json?lang=zh" --- # A 36.680 MHz FT8 Beacon Is Testing Autumn F2 Propagation: How to Listen, Log, and Interpret the Results > A 10-watt FT8 beacon in Lithuania will remain active through December 9 to test whether F2 propagation can reach 36 MHz. Here is a disciplined receive-only method for separating real openings from noise, decoder artifacts, and local interference. A small propagation experiment now offers a useful challenge for operators who have spent years watching the familiar 10-meter and 6-meter boundaries. Gintas, LY2YR, is transmitting a 10-watt FT8 beacon from Lithuania on 36.680 MHz from October through December 9, 2026. The stated question is whether ionospheric F2 propagation can carry a weak signal at a frequency this high, outside the usual amateur-band routines for most readers. Reports from outside Europe are especially welcome. ![Receive-only SDR monitoring station displaying a 36.680 MHz FT8 signal and an ionospheric propagation arc.](https://publicasta.com/storage/projects/40/pages/844/2026/10/72d9d128-3b03-49eb-829b-e50e3a9bdeb8.webp) This is not a new amateur band, a new FT8 calling frequency, or an invitation to transmit. For many operators, the appropriate participation is receive-only: tune a receiver, run a decoder, record UTC and signal details, and submit a report through the experiment's designated channel. The frequency sits in a part of the spectrum whose allocation and permitted use vary by jurisdiction. A receiver can be useful for radio science without giving an operator authority to transmit there. The experiment is timely because autumn propagation is easy to misread. Sporadic-E openings can still occur after the main summer season, while F2 propagation is governed by a different part of the ionosphere and is strongly dependent on solar illumination, ionization, frequency, geometry, and path length. A single decoded line will be interesting. A carefully documented series of observations will be much more valuable. ## What is being tested The beacon is specified as follows: - Frequency: 36.680 MHz - Mode: FT8 - Transmit power: 10 W - Location: Lithuania - Antenna: multiband hexbeam covering 20 through 6 meters - Reported beam heading: approximately 290 degrees - Test period: October 2026 through December 9, 2026 These details come from the announcement by EI7GL, which reproduces the information supplied by LY2YR. The broad radiation pattern of a hexbeam means that the stated heading should not be treated as a narrow point-to-point microwave-style beam. It remains relevant when comparing reports, but a station outside the main direction should not automatically conclude that reception is impossible. Antenna height, polarization, local terrain, receiver sensitivity, and the actual ionospheric path can matter as much as the nominal heading. The central propagation question is specific: can a signal near 36.7 MHz use the F2 region of the ionosphere for a path long enough to reach a distant receiver? NOAA's space-weather glossary defines foF2 as the maximum ordinary-mode frequency capable of vertical reflection from the F2 layer. That definition is a useful starting point, but it does not turn a foF2 value into a guaranteed communications path. Oblique-incidence paths, electron-density gradients, absorption, takeoff angle, and the geometry of the transmitter and receiver all affect what actually arrives at the antenna. The experiment is therefore best understood as a controlled observation of an unusual path, not as proof that 36 MHz is generally open. If a decode appears, it may be evidence that the path supported the beacon at that moment. It does not establish a permanent band characteristic, and it does not identify the exact mechanism without additional observations. ## Why FT8 makes the test practical FT8 is suited to this kind of work because it provides a standardized, time-synchronized signal that can be detected below the level at which a casual listener would confidently identify a voice transmission. The current WSJT-X user guide describes FT8 as using 15-second transmit/receive sequences. Its decoder reports useful metadata such as UTC, signal-to-noise ratio, time offset, and audio frequency. Those fields turn a fleeting trace into something that can be compared between receivers. That advantage comes with conditions. A computer clock that is several seconds wrong can make a real signal appear absent. Incorrect audio calibration can put the signal outside the decoder's search window. A receiver whose AGC is being driven by a nearby strong signal may show an attractive waterfall while losing weak decodes. A decoder message is evidence of a digital pattern that met the software's criteria; it is not, by itself, a complete description of the propagation path. WSJT-X 3.0.1 is the current general-availability release listed by the project when this article was researched. Older versions may still decode ordinary FT8, but keeping the software version, operating system, sound-card rate, and decoder settings in the log makes later comparisons easier. If the beacon operator specifies a particular implementation or reporting format, follow that instruction over a generic workstation setup. The important distinction is between monitoring and making a QSO. A beacon experiment may use an FT8 waveform because it is easy to detect and standardize, but the signal should not be treated as a normal contact opportunity. Do not answer it, call CQ on the frequency, or enable automated transmission unless you have verified that the frequency and emission are authorized for your station and that the experiment explicitly calls for it. ## A receive station that produces useful evidence You do not need an elaborate contest station to participate, but you do need a repeatable setup. Start with a receiver that covers 36.680 MHz and can provide a stable, narrowband IQ or audio output to WSJT-X. A transceiver in receive mode is acceptable when its frequency display and oscillator stability are understood. An SDR can be convenient because it allows you to watch the whole local passband and preserve an IQ recording, but a conventional receiver can produce equally useful reports if its calibration is reliable. Use an antenna that is safe and suitable for reception at the site. A short vertical, a broadband receive antenna, a dipole, a loop, or a multiband directional antenna may all reveal the beacon under different noise conditions. Do not infer that an antenna is ineffective merely because it does not resemble the transmitting antenna. The experiment benefits from reports made with ordinary installations as well as from high-performance stations. Before looking for the beacon, document the receiver chain: - Receiver make and model, or SDR hardware and driver - Antenna type, height, orientation, and approximate location or Maidenhead locator - Feed line and any preamplifier or filter in use - Sample rate and audio-interface settings - WSJT-X version and operating mode - Computer time source and measured clock offset - Local noise level and any recurring interference The goal is not laboratory perfection. The goal is to make it possible to distinguish a change in the path from a change in the station. If the preamplifier was switched on halfway through an observation, record that fact. If a household device, solar inverter, broadband adapter, or nearby transmitter changes the noise floor, record it instead of silently treating the resulting gap as a propagation failure. Set the receiver frequency carefully. A displayed frequency can differ from the actual tuned frequency because of oscillator error, SDR correction, transverter offsets, or an incorrectly configured CAT connection. Confirm the calibration against a known signal or a trusted frequency reference. The beacon's nominal frequency is 36.680 MHz, but the exact signal placement within the receiver's passband should be confirmed from current experiment information and from the waterfall. Do not shift to a presumed FT8 watering-hole offset simply because that is familiar from the amateur bands. ## Time, bandwidth, and decoder discipline Synchronize the computer clock before an observation session and check it again if the decoder produces no results. FT8's timed sequences make timing errors particularly costly. A weak signal that arrives with the correct frequency but the wrong apparent time may never become a valid decode. Record the time source and the observed offset, not just the fact that the operating system said it was synchronized. Configure the waterfall so that the decoder covers the region where the beacon is expected. Avoid an unnecessarily broad search window if the computer is struggling, but do not narrow it so aggressively that a modest frequency error hides the signal. Use a sensible audio level and avoid clipping. A receiver gain setting that makes the waterfall look dramatic can reduce the quality of weak-signal decoding. A practical first session can run for several hours rather than a few minutes. Leave the receiver untouched, capture the decodes, and note the UTC intervals when the path is open. If your software supports saving WAV or IQ samples, preserve short samples around an apparent decode and around strong non-decode periods. Samples are particularly useful when two operators disagree about whether a line was a valid decode or a false positive. Do not repeatedly restart the decoder every time a 15-second period produces no message. A long unbroken run provides a better record of intermittent openings. If the computer cannot process the signal continuously, state the duty cycle in the report. A station monitoring only five minutes per hour cannot be compared directly with one monitoring all day. ## How to separate F2 from other explanations A reception at 36.680 MHz will not identify its own propagation mode. Autumn sporadic-E remains possible, and the path may also include a combination of mechanisms. Local electrical noise can create lines in the waterfall. Receiver overload can produce intermodulation products. A software decoder can occasionally produce a low-confidence result when the passband contains a strong or distorted signal. These possibilities do not make the experiment uninteresting; they define what a careful report must leave open. Distance is an important clue. The EI7GL announcement notes that stations roughly 1,000 to 2,000 km from Lithuania may be well placed to catch a short opening, with southern European locations such as Greece and Italy mentioned as plausible examples. That range is not a guarantee, and it should not be used as a hard filter. A report from a different distance may be more informative precisely because it tests a different geometry. The timing pattern also matters. A short, sharply bounded reception with rapid changes over minutes could be consistent with an intermittent ionospheric opening, but it is not proof of sporadic-E. A broad regional set of reports appearing at similar UTC times is stronger evidence that the beacon was genuinely propagating beyond the local area. Reports from stations separated by hundreds or thousands of kilometres are more useful than a collection of repeated decodes from one receiver. Compare the event with signals on nearby frequencies when possible. Ten meters, 6 meters, and other beacon or digital activity can provide context, but they are not interchangeable measurements. A quiet 6-meter band does not rule out an opening at 36 MHz, and a strong local signal on another band does not prove that the same ionospheric layer carried the beacon. Use comparisons as supporting evidence, not as a substitute for the 36.680 MHz observation. Space-weather data can provide another layer of context. NOAA's current geophysical alert information for October 9 reports moderate conditions, recent R2 radio blackouts, and a forecast that includes a possible G2 geomagnetic storm on October 11. Such data can alter the ionosphere and may explain why one day differs from another, but a forecast category is not a local MUF prediction. Note the space-weather state alongside the observation and avoid claiming a causal connection unless the timing and geometry support it. ## A reporting format that other operators can use A useful report should be compact, precise, and reproducible. At minimum, include: ```text UTC date and time: Receiver frequency as displayed: Observed signal frequency or audio offset: Mode and software version: Decoded callsign or message: SNR and DT as reported by the decoder: Receiver and antenna: Location or Maidenhead locator: Noise and interference notes: Recording available: yes/no ``` If the decoder displays a confidence indicator, include it. If the line was visible but not decoded, describe the trace without converting it into a claimed reception. A screenshot can help, but a screenshot without UTC, frequency scale, and receiver details is much less useful than a plain text report with those fields. Use the same clock reference throughout the project. UTC is preferable because it avoids local daylight-saving changes and makes reports from different countries easy to align. Keep the original log file rather than copying only the most interesting lines into a spreadsheet. A complete negative record can be valuable: it tells researchers that a properly configured receiver was listening during a period when no beacon was decoded. If you submit a report to the experiment organizer, follow the current contact or form instructions in the original announcement. Do not assume that a spot on a public reporting site automatically reaches LY2YR. If you publish your own results, distinguish between an observation, an interpretation, and a conclusion. “FT8 decode at 36.680 MHz from locator X at 1132 UTC” is an observation. “Likely F2” is an interpretation. “This proves the F2 layer routinely supports 36 MHz” is a much stronger conclusion that the available evidence may not justify. ## What operators should not do The unusual frequency is the point of the experiment, and it is also the main regulatory hazard. Amateur allocations are jurisdiction-dependent. The United States, European countries, and other administrations do not necessarily provide the same privileges at 36.680 MHz. The fact that a signal can be received, or that a beacon announcement appears in an amateur-radio publication, does not grant a reader permission to transmit. Stay in receive mode unless you have independently confirmed that your license, location, equipment, emission, and frequency are authorized. Do not answer the beacon. Do not use an automatic sequencer. Do not test your transmitter by sending a carrier into an unknown allocation. If you are building a receive-only SDR, a recorder, or a passive antenna system, the safety and compliance questions are simpler, but normal electrical, RF, and antenna precautions still apply. Do not climb an antenna or alter outdoor equipment during poor weather simply to improve the report. A marginal improvement in signal level is not worth an avoidable fall or an improperly secured mast. For a multi-month receive experiment, station reliability and a clean log are more valuable than a hurried antenna adjustment made after one missed decode. ## A four-week observation plan A structured plan makes this experiment approachable for a club or an individual operator. In the first week, verify frequency calibration, computer time, decoder configuration, and noise documentation. Listen at several UTC periods and record both positive and negative results. The purpose is to establish that the station can run unattended without losing time or saturating the receiver. In the second week, keep the station configuration fixed and extend the monitoring window. Compare your results with public spots or reports only after preserving your own raw log. This prevents an attractive report from changing what you remember hearing. If another station reports the beacon while you hear nothing, check whether both receivers were listening at the same UTC interval and whether the paths are geometrically comparable. In the third week, make one controlled change, such as switching between two receive antennas or adding a known filter. Do not change the antenna, gain, software version, and clock source at the same time. A single controlled change can explain a difference; a collection of simultaneous changes cannot. In the fourth week, summarize by UTC hour, signal strength, distance, and station configuration. Count unique observation intervals rather than treating every repeated decode in one opening as a separate propagation event. Mark uncertain lines and do not discard negative sessions. If a local operator group is participating, compare synchronized logs and look for events that appear across stations. This approach also gives the project a useful DIY-electronics dimension. An inexpensive SDR, a carefully built filter, a stable reference oscillator, a low-noise power supply, or a simple receive antenna can all become part of the measurement chain. The experiment rewards improvements that are documented and repeatable. It is less useful as a contest for the loudest waterfall or the longest claimed distance. ## What a successful result would—and would not—show A credible reception would show that the beacon's signal reached a particular receiver with enough integrity for the decoder to identify it at a particular time. Several independent reports would establish that the signal was not merely a local artifact. A pattern across distance, UTC, and solar or ionospheric conditions could support a more detailed propagation analysis. That evidence still would not produce a universal prediction for 36 MHz. The result could depend on the beacon's location, antenna pattern, transmitter stability, receiver network, season, solar cycle, and the unusual path geometry. Even a month of successful reports would not mean that every station should expect daily F2 openings at that frequency. Conversely, a quiet month would not prove that the mechanism is impossible. The best outcome is a dataset with enough detail for other operators to reproduce, challenge, or extend. The beacon provides a fixed signal source; the community supplies geographic diversity. Those two features are more important than any single spectacular decode. For operators who normally spend their digital-mode time on 20 meters, 15 meters, 10 meters, or the conventional 6-meter FT8 segment, this is a chance to practice a different habit: treat the receiver as an instrument, not just a contact machine. Lock the clock, verify the frequency, preserve the negative observations, and report exactly what the decoder and antenna system showed. The result may be a rare autumn opening, a lesson in receiver limitations, or evidence that the path needs a different explanation. Each is useful when the record is honest about what was actually observed.