Cal really interesting isn't it. I enjoyed our research. 1. Tamitha's data is the dealbreaker for me - the correlation is too exact as the phenomenon she presents is too specific not to be the main culprit. 2. The YT delay was MUCH longer than the "live" RF reception I experienced. 3. Something strange was occurring that day as I had you 5/8 on 20m at 40 miles away. 4. The geographical spread of witnesses is interesting too. LDE's are fascinating. Ultimately nobody has an explanation. For a taster - here is a very in-depth PowerPoint talk from Sverre Holm, emeritus professor of acoustic imaging and signal processing at the University of Oslo F/LA3ZA in 2009; www.arp75.org/wp-content/uploads/2014/02/lde_la3za_arp_20090318.pdf
Thanks, Cal! You may be familiar with maritime coast station KPH in California, It was a commercial maritime station that closed service in 1997. The station was effectively abandoned in place. Because it was located (by then) in a national park the US National Park Service eventually took ownership of the station. A very dedicated group of enthusiasts persuaded the NPS to allow them to restore the station and put it back on the air as a living history museum. Some of the transmitters are operated in the amateur radio service, The station operated in Morse in full-duplex mode. In fact, we listened to our own signals as the effective "sidetone." Normally, this worked very well, except on higher frequency bands where the transmitter site was already outside the effective ground wave propagation zone, It was not unusual to notice a similar phenomena that you referred to in your video, If memory serves this was most pronounced on the 17m band, The delay was longer than what you would expect for long path propagation (as you also have observed), The information from Tamitha is helpful in perhaps explaining this .... Perhaps the signals are being "caught" in magnetic field lines. We were lucky that we were running the legal limit (1500w) and had excellent receive antennas and an incredibly quiet noise situation. As you can imagine, this could be a bit disorienting when you are sending Morse! I hope this video catches the interest of the HamSCI community! 73, Steve M0KKB/W3SMK
In 2004 I was living in Helena, Montana. I was working CW over the pole to Russian and Eastern EU stations on 20 meters. My antenna was a Cushcraft A3 S yagi with the 40 meter add in kit. The yagi was up approx 30 feet. The antenna was more or less aimed true north. This was in the Fall, the noise floor was very low. Around 17:00 UTC working stations for about an hour I began to hear my own call coming back to me after about two seconds. This persisted for a solid 10:00 minutes. The delay began to become longer, a solid four seconds after sending. It really couldn’t be anyone attempting to cause havoc. This phenomenon persisted for a good 10:00 or so minutes after the echos began to become longer in delay. It was also compounded by my CW signal being warped by magnetic north. It was insanely creepy and incredibly awesome. I’m very happy that I got to experience this phenomenon first hand. 73 de N1XV
Hi Cal..A local ham in Bristol was demonstrating a cw cq call for me, as a young lad, back in 1956 on 10 metres. Conditions were perfect and the noisefloor on his AR88 was nil.. The 'echo' was crystal clear. When I queried it, he was totally nonchalant, because he had heard it so many times before..He put it down to his own signal, circling the Earth, plus bounce.. No web sdrs or recording back then..73..John..G4EIJ
I've read about this phenomenon starting back in the 60's. The last article was a small blurb that NASA detected ducting in the magnetosphere that would guide a signal deep into space and take it back to the southern hemisphere where it would reflect off the ionosphere and head back into space. Eventually it would take it back to the northern hemisphere where it pops through the ionosphere and you hear it. If that is what happened, you are lucky to have experienced this elusive phenomenon.
Wow, that's amazing stuff. there's bound to be some uncommon propagational anomalies during the solar cycle peaks. Dr. Tamitha Skov's perfunctory response is top notch research on the subject. I'm surprised you heard your own signal, because it sounded like there was a lot of scatter weakening the signal bouncing around the path it took to return to you up near the Northern polar regions. Good stuff, nice catch.
I heard the tail end of myself 63 years ago while running phone patches for the guys in Antarctica on 40 meters and running about 300 watts . Lee, WA8QFE
Fascinating! I've been almost haunted by experiencing this myself back around 1990 on 80 M. Luckily, at least one other person in the QSO heard it at the time and asked "Is someone recording us?" It gives you chills, trust me.
Hi Callum, I experienced a LDE about 10 years ago. Pretty fascinating to hear. I recall the delay was about a half second after my transmission. Great stuff! Denis, W1WV
Had the long duration echo happen several times to me during various Radio Contests here in Alaska. About a 2 second delay and I think was on 80m, perhaps 40m? Very startling the first time you hear yourself. Tamitha is masterclass.
Hi When I was like 16y old I did play around with 11m radio had one og these president ssb radio’s and a 5/8y antenna. It was solar max. at that time (remember talking with a truck driver in New York 4w FM from Denmark). Anyway it had “Roger beep” enabled, one day I did get the echo from the beep, it was just bit less than a 1sec after PTT release- did think that it was my signal that went around the earth. Best regards OZ5KR
This happened to me using a 4 element quad on 10 meters. It led to me realizing that I could work long path, even if I couldn’t reach it short path. I then worked JA’s at 120 +- degrees from Atlanta, when the propagation wasn’t good at 290 degrees. I think the terminator was part of it. This was back near the solar peak 2 cycles ago. Now you’ve got me wanting to rebuild that quad again, though I don’t think 28 MHz is as good now. You might want to ask Tamitha about the magnetic pole shift and weakening mag field strength around Earth.
Thinking about it further, the timing is about right for an echo off the moon. Have you looked at something like stellarium to see where the moon was at the time this was happening? If that solar wind magnetic polarity flip did open up the ionosphere allowing HF through, this would be really interesting. As far as I know nobody has ever done an experiment to see how good the moon is at reflecting HF frequencies. You have to be outside of the ionosphere to test that. Maybe the moon is an exceptionally good reflector at lower frequencies?
Hiya Kevin.. Yes, the moon. It would be fun and someday I might do my own private experiments! Anyway, I just checked with ChatGPT (I call him George) thinking that the back of the Yagi could do this.. "Hey George.. Assuming I am in the middle of England, do you happen to know exactly where the moon would have been in respect to my location on 4th January at exactly 12:30UTC? ? I did once work out it was at around 8 degrees off the horizon and roughly south east to me. Can you check that?" - HIS REPLY WAS "On January 4, 2025, at 12:30 UTC, in central England, the Moon was in its Waxing Crescent phase, approximately 23% illuminated. It rose at 10:56 UTC and set at 21:10 UTC. At 12:30 UTC, the Moon was about 8 degrees above the horizon, positioned roughly toward the southeast. Your previous calculation aligns well with these details."
There is a video clip of some guys in Poland who built a huge multi yagi multi element array for 15 meters. They were able to get S7 reflections back from the moon.
Hi Callum, yes I have had this happen to me back in the early 80’s. It was on 15m ssb, I was beaming shortpath to Japan, if memory is correct it was about 11 am, dont remember the time of year unfortunately. The echo was slightly shorter in duration than yours and was only present for about 15 minutes. Cheers, de Colin, G4MQK
Ciao, I've small station and no working antennas on 80m, but this video was very, very interesting - thanks a lot to share it - propagation is a field you can never master... we understand very little of it and this is why it is so interesting and charming! 73s Davide
my late uncle, told me he had a similar experience, he was an RAF radio operator, and he said he once dropped the key and heard himself coming back a second latter, he put it down to a straight skipping round the world
This is an amazing coincidence. QST magazine (published by the ARRL in the USA) in the February 2025 issue on page 30 has an article entitled, "Further Observances of Long-Delayed Wireless Echoes." The author details research he did in 1978, 1996, and 2022 along with listing articles he wrote and published in the intervening years. He discusses several theories and possible interacting factors in LDE.
I once experienced a VERY long delayed echo of hearing myself a full day after I had last sent a CQ. I was preparing to call CQ on an 80 meter frequency that I regularly would operate on and while listening to the frequency to be sure it was clear, I heard someone calling CQ and then I heard my call being signed! The fist sounded just like mine. This went on for a few minutes and then stopped. Then it started up again! I remembered that I had called CQ twice on the same frequency at about the same interval the night before. To make a long story short, it turned out that while I was operating on the previous evening, my wife was recording a show on our VCR. At the time I heard my mystery echo, she was playing back the show on the VCR. Apparently the 80 meter RF from my CQ got into the VCR and was recorded onto the video tape as a CW signal at my operating frequency, and when the video tape was played back, the signal was re-radiated (quite strongly by the way) by the VCR!!!! AJ1G Stonington CT
That's kind of amazing! Both for the effect in and of itself, and for your detective work in finding the explanation. I'm not really a true radio guy, but it must have been quite the head~scratcher at the time (not to say, spooky!) It reminds me of the story (you may well be familiar with it, if so, forgive me!) of the radio astronomers who picked up an anomalous signal, repeating itself at regular intervals. Scrupulously they went through lists of satellites, possible military, aviation, business, etc. users, but it got so that, almost for the want of any other explanation, they were starting to wonder, in almost hushed tones, "Could it be - could it _really_ be - _extra terrestrial_ in origin?!" By which I actually _do_ mean aliens, as opposed to signals bouncing back off of the moon, Jupiter's magnetosphere, anything like that! Like good scientists are supposed to though, they continued to do their best to investigate and exclude every possible other contender before even talking out of school, let alone holding press conferences or anything like that (or maybe they were just afraid that some guys in dark suits might visit them and give them a mind wipe!) Anyway, it is as well that they did, for it would prove that they were eventually able to isolate and track down the elusive and intriguing signal... to the break room, where a colleague, presumably occupied on a different project, was warming his lunch in the microwave!
I had the same thing happen in October 2023, on 10m, 50w, mobile, SSB. I was listening to a station just far enough that it was too far for ground wave and he had a weird sort of warble to his audio. I heard his signal echo and realized I was copying him long path. I went up a little in frequency and heard a Bulgarian station like he was across town (I’m in Pennsylvania). That’s when I heard my own echo. I’ve heard it called LDE/Long Delay Echo-the signal actually goes around the world several times before fading. This was about 11:00 am local time.
Back in the 90's I made a contact with a gentleman on the east coast of the United States, and he was working contacts for long path contacts. He didn't want to make contacts with people unless he was hearing the long path echo. It was really crazy, he explained it to me what he was doing and I listened to him for probably an hour.
I haven't heard my own echo recently but years ago whenever I was first starting out on HF, I did one day on 20 meters and I'll tell you it was one of the weirdest things I've ever heard. Great video 73 👍🙂
Hi Colm, I also have this happened to me in the 80s while I was Mobile. I can’t remember the frequency. I like you at the time assumed it was a troublemaker or something but I now know it was quite an experience with a very loud delay of about five seconds but because it was so clear and loud I did naturally assume I was being recorded, I was told it was Myself hearing myself hopping around the world.🌎 😮
Haven’t seen it mentioned yet specifically in comments but if you are listening to your own signal come in your receiver just after you unkey, it may simply be a result at digital processing latency. If I simultaneously listen to my transmitted audio from a local transmitter in an analog receiver and an SDR based radio such as my IC-7300, I can hear a distinctive echo/ reverberation effect. The echo effect is even more extreme when using an 8bit dongle based SDR that I run on the iMac desktop shack computer. I cannot use either the 7300 or the 8bit SDR as a sidetone for a standalone CW transmitter because of the latency effect. Any remote internet SDR one uses will have latency when listening to a transmitter you are keying from your location. The Kiwi SDRs all have about a 3 second latency, you can use that latency to monitor yourself , if you are muting a Kiwi SDR while transmitting, the last three seconds of your transmission will be audible when you unkey. Of course you can also record yourself on the Kiwi SCRa and have them send you a .wav file of the recording. AJ1G
I'm not finished with the video yet, but when I was in the army working HF this was quite frequent. We were told it was tropospheric/ionospheric return, or the long path reach. Most often occurring slightly below 10 m and slightly above 40 m. Now I'll watch the rest of the video and see what you come up with.
Heard it on day 2 as an Amateur. I squeezed a highly directional miniature V beam into my garden and was astonished at the delayed echo. Changed frequencies a couple of times and still heard. On 20mtrs from memory but might just have been 15.
I think anyone who has been on HF for a while has heard this before. It's not always super obvious like half a second or several seconds like this one. I hear it very often on European stations here in Alberta, especially on 20 meters and lower in frequency. Sometimes on 10M but not as often and the delay is much shorter on 10M typically. It usually sounds like the operator is in a big empty room with all hard surfaces like the echo or reflection is local to the operator and microphone being used. But upon hearing that exact same station at the same time on say a remote SDR somewhere else in the world, or even a recording replayed by another station back to them, the audio is very dry with 0 room echo. From that I know that the operator and microphone are not causing or picking up room reflections and that it is a longpath verses shortpath echo or something else causing long reflections to occur. Sometimes I will hear the same operator at a different time and the audio is bone dry without any room sound at all. If one has any experience with recording using microphones in a room you will understand how this works. Yes, an RF signal can go around the world 7 times in one second which would perhaps make one believe that it would be nearly impossible to hear an echo, but you need to take into account how signals propagate and reflect (bounce) around the ionosphere and the earth. That signal might bounce a thousand times on it's way back to you and each one of those bounces takes a little more time. I absolutely guarantee that your experience here was not someone rebroadcasting your audio from somewhere. Too many people heard the delay in too many random places for it to have been a station rebroadcasting. Also, the delay time variation was totally different and unique for everyone, even within your own audio examples. If it were a station rebroadcasting, everyone would have heard it at the same time and the delay time would have been more consistent on each transmission. An automated rebroadcast would have been an exact delay time, every time. A person clicking a mouse or something might have had some variation in the delay time, but not like this. It was a naturally occurring phenomenon. A phenomenon reasonably well explained by the space weather expert as well. I'm not sure 47 minutes is a natural phenomenon as there is inertia involved and that will eventually cause the signal to degrade past the point where it can propagate, or at least too weak for our equipment to receive at any rate. I suppose it could have been a planetary reflection but that's improbable in the extreme for so many reasons.
I haven't observed echoes as long as yours but I've often had them around 250ms around dusk on 15m and 17m in the last couple of years, and around sunrise on 15m. I can listen to myself on the web SDR down at Weston-Super-Mare and hear the ground-wave and delayed signal quite plainly, to take any local effects out. The effect works for 15 minutes or so and then as it gets darker it dies out. I have got a few recordings somewhere I have meant to do a video on - I have one very sketchy video up on my channel of 15m morning weirdness from before I started trying to analyse this properly. This is all from my portable spot by the harbour where at least some of my RF is going out at very low angles indeed.
An SWL during the mid 1990s told me about these "round the world" echoes. Apparently, on CW, it can confuse the receiving station as it can sound like several stations transmitting at once. This often leads to the transmitting station being told to slow down their speed QRS (I believe), to help eliminate this phenomena and make their transmission more readable.🤔
That's all very well Cal, but when you cut the TH-cam stream audio, the phenomenon went away, so I'd swing towards broadcast from the stream. By whom and where, I don't know.
Happened to me while operating mobile on holy island last year . I was using a Yaesu ft 857d and a chameleon MPAS on 17m it was on all signals as well as my own when calling CQ. I definitely think yours was an LDE especially because the echo was immediate heard after your transmitting had ended if it was someone recording and retransmitting there’d be a much longer delay that was immediate
Back in the mid 1990s (before I left the hobby for a long time) I recall conversations on 10 and 11 meters that had doppler shift, and delays on signals. Very occasionally an echo from the other station. No mechanical help there either.
You will sometimes notice huge doppler on some arctic signals via the auroral belt. At other times you canl hear echo when you receive SP and LP from the same station, but this is normally 130ms or less difference. Nothing like this video. I have even worked a friend of mine LP on 20m SSB. He was only 60km away, but the distance over the air was 39940km :)
As I told you live in chat, it was someone rebroadcasting your audio from TH-cam. The delay was consistent with the one from your live streaming, and when you muted your youtube audio, the "echo" was gone. Moreover the transmission bandwidth was different and with a different equalization; in my receiver the "echo" signal was stronger in some bands while maintaining its recognizable bandwidth and EQ. I'm quite sure it wasn't a natural phenomena.
@@xanderlewis People create all sorts of QRM on Cal's streams, and the streams of several of the TH-cam ham radio fraternity. I guess they just don't want anyone to have fun.
one simple little experiment you could try. Naturally you aim your beam towards where you expect a response, eg VK, but how about trying to send it over a path that included the maximum amount of sea and minimum land to see if it 'bounced better' and came back round. say, just east of Greenland and then do the same thing when there are reports of strong aurora to see what happens.
I do know how odd DX can sound at times. In my early General class days I was working CW on 15 meters in the afternoon and I was hearing the normal US CW chatter on the band. Suddenly the band went quiet and the US CW signals went silent - like when you are in the forest at night and the crickets and frogs go silent... I sent CQ and a very faint and warbly signal came back to my call from Novosibirsk. That was my first ever DX contact. About 5 minutes after the end of the QSO the US signals came back and that was the end of it. I figured it was some kind of hop across the NP with aurora flutter involved giving the signal that strange sound, but it does not explain why the band went quiet though...
Yeah.. If you listen to my clip again at 0:50, you'll hear the band change for a few seconds and different skip zones quickly come in and out.. I can briefly hear another QSO, perhaps west coast that comes and goes.
I have had this happen to me back around 1987-1988 during a peak sun cycle. on 11meters from CU3 land. I don't recall what part of the world I was talking with now, but as soon as I let go of the PTT I heard myself.
Ap on that day were 9-27 meaning it still was not very calm conditions. If you want the least attenuated conditions on low bands you would like a positive DST (usually happens when it has been calm geomagnetic for many days). Echoes on 40m is common, but normally you can explain them with the normal 100+ milliseconds delays LP or skewed, and you can hear several paths at the same time (making CW decoding difficult). I do not buy that someone can JUST copy the echo travelling 15 times around Earth, and not all the others before (1-14) that should be stronger. I have not hear about echoes travelling more than two times around Earth, but I am sure it could be 2-3 times if power was high enough.
Most of the times I've heard long path it was at most the last letter or part therefore... However, I have had something similar happen once... Not quite as long as yours, but long enough to hear the number and suffix of my call sign (phonetically.) It took me by surprise. I thought something strange was going on and released the mic after saying "cq" and heard myself saying cq. Eerie.
Absolutely fascinating. I have experienced long path echo but never this delayed. It does sound dxy to my ear, and cannot understand why anyone rebroadcasting (as suggested elsewhere) would result in a single echo not multiples - in many places. There is still much we have to learn about propagation, and your experience as it ties up with magnetic events is really interesting.
@@g0jjg Audio taken from TH-cam while Cal was speaking, may only create a single echo; no feedback issues or anything else because it was only his voice.
@@alexr71 I now query this rebroadcast. Only *my* signal was being rebroadcast, not the other participant - and folks hearing multiple different times of the repeat from half a second and up - also "both paths" confirmed.. It came and went pretty quickly and when I started testing it out, it dropped off altogether.
@@DXCommanderHQ I see your point, but... I think the delay time reported in chat was approximate and I think it was reported as different from person to person only because of that approximation. Delay time was around 3.15 sec (I had a chronometer) and it was really consistent with TH-cam delay (you can check it under "stats for nerds" during the live streaming). At the start of the "echo" signal, I could hear clearly a particular noise just like when you use a amplifier; that noise was not in your audio. Furthermore bandwith and eq were different. The "echo" signal was clear, without any distorsion or shift in frequency, and I can remember when you changed band it was louder than yours. Rebroadcasting your audio from youtube without taking other sounds is not difficult; just hit the PTT at the beginning (it doesent matter if the timing is not 100% right) and just drop it when you stop talking. In your streaming there is around 1 second delay at the end of your TX, so it's easier to rebroadcast it. I would love to see the full stream again, but in any case the ultimate test would have been to broadcast by surprise without transmitting the audio in the live; if there had been no echo in that case, you would have had the final answer. I stand by my theory due to the inconsistencies with a natural phenomenon, but at this point it is impossible to prove either hypothesis.
@@DXCommanderHQ I see your point, but... I think the delay time reported in chat was approximate and I think it was reported as different from person to person only because of that approximation. Delay time was around 3.15 sec (I had a chronometer) and it was really consistent with TH-cam delay (you can check it under "stats for nerds" during the live streaming). At the start of the "echo" signal, I could hear clearly a particular noise just like when you use a amplifier; that noise was not in your audio. Furthermore bandwith and eq were different. The "echo" signal was clear, without any distorsion or shift in frequency, and I can remember when you changed band it was louder than yours. Rebroadcasting your audio from youtube without taking other sounds is not difficult; just hit the PTT at the beginning (it doesent matter if the timing is not 100% right) and just drop it when you stop talking. In your streaming there is around 1 second delay at the end of your TX, so it's easier to rebroadcast it. I would love to see the full stream again, but in any case the ultimate test would have been to transmit by surprise without broadcasting the audio live on youtube; if there had been no echo in that case, you would have had the final answer. I stand by my theory due to the inconsistencies with a natural phenomenon, but at this point it is impossible to prove either hypothesis.
@@DXCommanderHQ I wrote you a detailed response twice, but I don't know why TH-cam deletes it instantly; I'll try to change some words and see if it will be published...
Okay, third comment, but I just went and looked at an EME video where a guy was hearing himself bouncing off the moon, and the delay was almost identical. Nearly 4 seconds just counting out loud. I'll have to get my laptop out and grab the video clips and actually time it in the video, but you might consider doing the same with some of these EME videos that are out there. Cuz it certainly looked to me like exactly the same delay. If that's the case, that would make the moon a candidate.
@@DXCommanderHQ Well the next thing to do would be to look at where the stations were that heard the echo and where the stations were that could not hear the echo, and then look at where the moon was. If the stations that could not hear it were on the opposite side of the Earth from the Moon, that would make sense. And also you've got your original video so you can do the timing better, but go look at some of the UHF VHF Moon bounce videos where they hear their own echo and compare the timing. Perhaps that event Dr Skove pointed out did allow HF to pass through the ionosphere. We could be contributing to solving this mystery.
@M0RMY I'd have to go look through my history, but it was somebody copying moon bounce of their 10 m CW transmission. And I also looked at one of a guy doing VHF voice, but there's many of these videos out there. The timing should be the same in every case.
@@DXCommanderHQ Another thought that occurred to me, made the hair on the back of my neck stand up. Why does the ionosphere reflect HF frequencies back down? Because it is charged up by the solar wind. So if the magnetic pole in the solar wind reversed, well wouldn't there be a short period where the ionosphere's charge dropped and then came back up reversed? Wouldn't there be a short period of time where the charge was basically neutral as it was flipping, and during that time perhaps it could allow HF through. This is really starting to make sense.
There’s a RADCOM article about this effect written in the late 80’s called ‘AMTOR spins a time warp around the earth’ where an AMTOR broadcast was sent and then received itself a few seconds later, the effect was a long path signal travelling around the earth. If the circumference of the earth is taken and divided by the speed of light the result is about 1.4secs, then extend the distance to account for multi-hops and the delay is about what you were experiencing. I think there is nothing particularly unusual about these events.
In 1966 I experienced a 20 second delay on 15 meters. This effect repeated for about 15 minutes. To rule out any kind of rebroadcast I kept changing the frequency and the echo still kept returning. An asteroid bounce perhaps?
Yep. Have heard this but much shorter... "CQ CQ CQ 2 echo zero papa tango yankee" release the PTT and hear a strong "o yankee"... Thought it might be a global bounce.
very interesting. I'm afraid we will never know for sure what it is. The more you talk about it the more some funny guys will rebroadcast your stuff now 😂
Completely off topic- sort of - But i wonder if this anomaly was the inspiration for the movie "Frequency" starring Dennis Quaid and Jim Caviezel about a Son of a Ham radio operator talking to his father from the pass from his old ham radio set cause by solar effects etc. Great movie if your a Ham or CBer you may really enjoy this movie! I sure did.😉
Well the delay is far too long to be propagation around the planet. It takes about two tenths of a second for a signal to make its way around the planet, 25,000 mi or so at 186,000 miles per second. The information from tamatha was very interesting. Normally HF does not make it out of the ionosphere. Perhaps that shifting of the magnetic field polarity in the solar wind punched a hole in the ionosphere that HF signals could get through allowing them to go out and bounce back off of something else like the moon or some outer band of magnetic field or ionized radiation. But that's just a guess.
You were broadcasting wirelessly, correct? Perhaps it was an internet issue. Perhaps your internet did the rebroadcast? Or your radios internet receiver system had a glitch.. Just a thought. Interesting stuff though!
I had a very similar experience a few years ago during a contest. I was calling cq contest and heard my voice repeating the cq. Being new to the hobby, it kinda freaked me out. I wasn’t sure what was going on. If I remember correctly, at that time I was running 100 watts and a fan dipole at roughing 35’. I don’t remember what frequency I was on. At that power with that antenna, I kinda doubt it was long path. So what was happening? 🤷🏻♂️. I only heard it a couple times. Thanks for sharing!
The information from Tamitha and the trimming lines up with what happened on radio time with that long duration echo. It was the flop in magnetic field which was recorded at that time. The magnetic field grabbed some of the RF and spun it around like a motor and set it back at a delayed time. This was done around the north magnetic pole . The North pole has been shifting so if using a compass to find santa claus at north pole will will get lost . I have hurd short echo on 10 and 11 meters talking DX and 6 meters as well. Makes a hard copy . Sounds like a echo mic turned up to much . And this did not happen south of equator. More proof of north magnetic pole. Great information given . Cheers ! santa just hiding his location . Many did not get what wanted for Christmas. I would hide as well . LOL
I heard a short echo on a German station who was calling CQ and thought he must have even running QRO and beam on 40 Mt's, I worked him and told him about the echo and asked about his station. He was only running100watts and an end fed wire. I thought it only happened with high power. I will check my log for the date, it was only a few weeks ago, but as it was from my mobile station I don't log the time. I was parked on the top of a river bank having a coffee break while at work at the time. He didn't comment about the echo so I don't know if he could hear it and I couldn't hear it during the QSO Ken G6YYN
I think you're hearing your signal make it around the earth and coming back to you. I have only heard this once while calling CQ on 15m a few years or so ago. I was able to briefly make qso's with Japan at the same time I heard my 'echo'. It didn't last long and at the time I was only running 100w barefoot. My qth is in PA, so I was excited about the japanese qso's as they aren't common for me.
This was my thinking also that essentially you are hearing yourself 'long path' ?? I don't know enough about how Temperature etc alters the speed of sound though to work out if this would account for the delay.
That would be a much shorter echo. It's about 25,000 mi around the Earth, and a radio wave would propagate that in under two tenths of a second. There was a much longer delay on this echo.
3.15s is 1000000km. Can‘t believe that your Signal could Travel as far. TH-cam transmit: no, because in that case other Parts of the stream would have been transmitted, too, not just your voice. Web sdr: Same here, at least Parts of other transmissions would have been heard. But it Must be man Made And automatic, otherwise the Delay would Not have been as constant. So propably a neighbor with a deaf rx And a remote tx .. 73
Hi, Cal. This may seem like a looney idea, but it popped into my mind as I considered the time factor and Tamatha's discussion. In the best case, the human hearing range is ~ 20 to 20K Hz. We also know that under certain conditions, vibrations will experience resonance depending on the geometry and consistency of the vibrating medium. So, what if, under the space weather conditions described by Tamatha, the electromagnetic signal essentially began to resonate in the plasma medium creating a self-perpetuating resonant echo, this resonance occurring across an extremely wide "bandwidth" with only the ~20 to 20K Hz segment being obvious to us as the self-perpetuating echo signal cycled through this large, resonant bandwidth. Consider the effect of bringing a crystal water glass to resonance by merely tracing a wet fingertip over its edge. As the resonance gains amplitude, less fingertip tracing is required to perpetuate and often increase the amplitude. With all that being said and considering the above hypothesis, could the space weather at the observed moment be creating a plasma condition somewhat similar to the crystal water glass, the electromagnetic R.F. providing the stimulus bringing the plasma to resonance thus "storing" and "retransmitting" the signal across this wide, oscillating bandwidth with only a portion of it being audible to us across time creating the "delay" observed as the large resonating plasma body worked its way through the vibratory frequencies? I hope that made sense.
On CB, I used to mess with people by recording the audio from a Web-SDR and playing it back 1-2 seconds later at the same time. It always sparked debates about this "phenomenon," lol.
Like loughkb, my money is on the moon, no, I meant check the position of the moon when you have that experience. Fun to think about! Oh! medication time? I'm doing that now with an IPA. Cheers AA7MO
@@M0RMY very little, we have warbling going on all of the time with local HF, if we are talking either local or dx, with aeroplane scatter. Usually when working DX...VK, JA etc, with quite an echo there's a good chance that lp or sp is better... depending which way you are beaming in the first place.
I once experienced a VERY long delayed echo of hearing myself a full day after I had last sent a CQ. I was preparing to call CQ on an 80 meter frequency that I regularly would operate on and while listening to the frequency to be sure it was clear, I heard someone calling CQ and then I heard my call being signed! The fist sounded just like mine. This went on for a few minutes and then stopped. Then it started up again! I remembered that I had called CQ twice on the same frequency at about the same interval the night before. To make a long story short, it turned out that while I was operating on the previous evening, my wife was recording a show on our VCR. At the time I heard my mystery echo, she was playing back the show on the VCR. Apparently the 80 meter RF from my CQ got into the VCR and was recorded onto the video tape as a CW signal at my operating frequency, and when the video tape was played back, the signal was re-radiated (quite strongly by the way) by the VCR!!!! AJ1G Stonington CT
Cal really interesting isn't it. I enjoyed our research.
1. Tamitha's data is the dealbreaker for me - the correlation is too exact as the phenomenon she presents is too specific not to be the main culprit.
2. The YT delay was MUCH longer than the "live" RF reception I experienced.
3. Something strange was occurring that day as I had you 5/8 on 20m at 40 miles away.
4. The geographical spread of witnesses is interesting too.
LDE's are fascinating. Ultimately nobody has an explanation. For a taster - here is a very in-depth PowerPoint talk from Sverre Holm, emeritus professor of acoustic imaging and signal processing at the University of Oslo F/LA3ZA in 2009;
www.arp75.org/wp-content/uploads/2014/02/lde_la3za_arp_20090318.pdf
I was hoping you would chip in Tom!
Thanks, Cal! You may be familiar with maritime coast station KPH in California, It was a commercial maritime station that closed service in 1997. The station was effectively abandoned in place. Because it was located (by then) in a national park the US National Park Service eventually took ownership of the station. A very dedicated group of enthusiasts persuaded the NPS to allow them to restore the station and put it back on the air as a living history museum. Some of the transmitters are operated in the amateur radio service, The station operated in Morse in full-duplex mode. In fact, we listened to our own signals as the effective "sidetone." Normally, this worked very well, except on higher frequency bands where the transmitter site was already outside the effective ground wave propagation zone, It was not unusual to notice a similar phenomena that you referred to in your video, If memory serves this was most pronounced on the 17m band, The delay was longer than what you would expect for long path propagation (as you also have observed), The information from Tamitha is helpful in perhaps explaining this .... Perhaps the signals are being "caught" in magnetic field lines. We were lucky that we were running the legal limit (1500w) and had excellent receive antennas and an incredibly quiet noise situation. As you can imagine, this could be a bit disorienting when you are sending Morse! I hope this video catches the interest of the HamSCI community! 73, Steve M0KKB/W3SMK
The important question, Cal,is, "Can you count it as a QSO?"😂
In 2004 I was living in Helena, Montana.
I was working CW over the pole to Russian and Eastern EU stations on 20 meters.
My antenna was a Cushcraft A3 S yagi with the 40 meter add in kit.
The yagi was up approx 30 feet.
The antenna was more or less aimed true north.
This was in the Fall, the noise floor was very low.
Around 17:00 UTC working stations for about an hour I began to hear my own call coming back to me after about two seconds.
This persisted for a solid 10:00 minutes.
The delay began to become longer, a solid four seconds after sending.
It really couldn’t be anyone attempting to cause havoc.
This phenomenon persisted for a good 10:00 or so minutes after the echos began to become longer in delay.
It was also compounded by my CW signal being warped by magnetic north.
It was insanely creepy and incredibly awesome.
I’m very happy that I got to experience this phenomenon first hand.
73 de N1XV
Hi Cal..A local ham in Bristol was demonstrating a cw cq call for me, as a young lad, back in 1956 on 10 metres. Conditions were perfect and the noisefloor on his AR88 was nil.. The 'echo' was crystal clear. When I queried it, he was totally nonchalant, because he had heard it so many times before..He put it down to his own signal, circling the Earth, plus bounce.. No web sdrs or recording back then..73..John..G4EIJ
Good point! Lots of stuff unreported...
I ran QSK CW 1000W and could use the antenna as a directional radar. Its normal via backscatter on the higher frequencies.
I've read about this phenomenon starting back in the 60's. The last article was a small blurb that NASA detected ducting in the magnetosphere that would guide a signal deep into space and take it back to the southern hemisphere where it would reflect off the ionosphere and head back into space. Eventually it would take it back to the northern hemisphere where it pops through the ionosphere and you hear it. If that is what happened, you are lucky to have experienced this elusive phenomenon.
Now that sounds more like it..
Wow, that's amazing stuff. there's bound to be some uncommon propagational anomalies during the solar cycle peaks. Dr. Tamitha Skov's perfunctory response is top notch research on the subject. I'm surprised you heard your own signal, because it sounded like there was a lot of scatter weakening the signal bouncing around the path it took to return to you up near the Northern polar regions. Good stuff, nice catch.
I heard the tail end of myself 63 years ago while running phone patches for the guys in Antarctica on 40 meters and running about 300 watts .
Lee, WA8QFE
Wow
Fascinating! I've been almost haunted by experiencing this myself back around 1990 on 80 M. Luckily, at least one other person in the QSO heard it at the time and asked "Is someone recording us?" It gives you chills, trust me.
Hi Callum, I experienced a LDE about 10 years ago. Pretty fascinating to hear. I recall the delay was about a half second after my transmission. Great stuff! Denis, W1WV
Interesting!
Had the long duration echo happen several times to me during various Radio Contests here in Alaska. About a 2 second delay and I think was on 80m, perhaps 40m? Very startling the first time you hear yourself. Tamitha is masterclass.
Way cool! Thanks for the video
I have heard of echoing before in hf bands, but never knew why. Thanks for the video.
Hi
When I was like 16y old I did play around with 11m radio had one og these president ssb radio’s and a 5/8y antenna. It was solar max. at that time (remember talking with a truck driver in New York 4w FM from Denmark).
Anyway it had “Roger beep” enabled, one day I did get the echo from the beep, it was just bit less than a 1sec after PTT release- did think that it was my signal that went around the earth.
Best regards OZ5KR
Brilliant.
In the 80's, I heard LDE in 11 meters.
Had a good friend who also heard himself echoing back in the 1980s solar peak
Yes do remember early 80s in 26 an 27 remember people saying that they could hear them self later,, now I know more
This happened to me using a 4 element quad on 10 meters. It led to me realizing that I could work long path, even if I couldn’t reach it short path. I then worked JA’s at 120 +- degrees from Atlanta, when the propagation wasn’t good at 290 degrees. I think the terminator was part of it. This was back near the solar peak 2 cycles ago. Now you’ve got me wanting to rebuild that quad again, though I don’t think 28 MHz is as good now. You might want to ask Tamitha about the magnetic pole shift and weakening mag field strength around Earth.
Thinking about it further, the timing is about right for an echo off the moon. Have you looked at something like stellarium to see where the moon was at the time this was happening?
If that solar wind magnetic polarity flip did open up the ionosphere allowing HF through, this would be really interesting. As far as I know nobody has ever done an experiment to see how good the moon is at reflecting HF frequencies. You have to be outside of the ionosphere to test that. Maybe the moon is an exceptionally good reflector at lower frequencies?
Hiya Kevin.. Yes, the moon. It would be fun and someday I might do my own private experiments! Anyway, I just checked with ChatGPT (I call him George) thinking that the back of the Yagi could do this.. "Hey George.. Assuming I am in the middle of England, do you happen to know exactly where the moon would have been in respect to my location on 4th January at exactly 12:30UTC? ? I did once work out it was at around 8 degrees off the horizon and roughly south east to me. Can you check that?" - HIS REPLY WAS "On January 4, 2025, at 12:30 UTC, in central England, the Moon was in its Waxing Crescent phase, approximately 23% illuminated. It rose at 10:56 UTC and set at 21:10 UTC. At 12:30 UTC, the Moon was about 8 degrees above the horizon, positioned roughly toward the southeast. Your previous calculation aligns well with these details."
As I said on the original video, 80m moonbounce!
There is a video clip of some guys in Poland who built a huge multi yagi multi element array for 15 meters. They were able to get S7 reflections back from the moon.
@@ianbuffham4006 Geez. I'll have to find that...
Tamitha's response was a masterclass.
Yes, lovely.. Thank you Tamitha!
Tamitha is quite the physicist, she reminds me of my dad, who explained a whole lot of sub-atomic physics to an eight year old child.
Really interesting and you really covered it well! Thanks for the video! I hope to hear more about it. LDE have always piqued my interest.
More to come!
Hi Callum, yes I have had this happen to me back in the early 80’s. It was on 15m ssb, I was beaming shortpath to Japan, if memory is correct it was about 11 am, dont remember the time of year unfortunately. The echo was slightly shorter in duration than yours and was only present for about 15 minutes. Cheers, de Colin, G4MQK
Nice.
I can tell you're a musician as soon as you started talking about tone! Tone is everything in music!
Ciao, I've small station and no working antennas on 80m, but this video was very, very interesting - thanks a lot to share it - propagation is a field you can never master... we understand very little of it and this is why it is so interesting and charming!
73s
Davide
Hi Cal.
I had the same thing about 15yrs ago. Very strange propagation indeed.
Great video Callum! I suspect this one might go viral😊
thanks for the meds reminder again. :)
Any time!
my late uncle, told me he had a similar experience, he was an RAF radio operator, and he said he once dropped the key and heard himself coming back a second latter, he put it down to a straight skipping round the world
This is an amazing coincidence. QST magazine (published by the ARRL in the USA) in the February 2025 issue on page 30 has an article entitled, "Further Observances of Long-Delayed Wireless Echoes." The author details research he did in 1978, 1996, and 2022 along with listing articles he wrote and published in the intervening years. He discusses several theories and possible interacting factors in LDE.
Wiggly RF and a Basket load of Bananas can do amazing things. Its fascinated me from a very young age. Some great info Cal 🙂
Glad you enjoyed it!
I had this happen to me one time years ago it was fun !!
I once experienced a VERY long delayed echo of hearing myself a full day after I had last sent a CQ. I was preparing to call CQ on an 80 meter frequency that I regularly would operate on and while listening to the frequency to be sure it was clear, I heard someone calling CQ and then I heard my call being signed! The fist sounded just like mine. This went on for a few minutes and then stopped. Then it started up again! I remembered that I had called CQ twice on the same frequency at about the same interval the night before. To make a long story short, it turned out that while I was operating on the previous evening, my wife was recording a show on our VCR. At the time I heard my mystery echo, she was playing back the show on the VCR. Apparently the 80
meter RF from my CQ got into the VCR and was recorded onto the video tape as a CW signal at my operating frequency, and when the video tape was played back, the signal was re-radiated (quite strongly by the way) by the VCR!!!!
AJ1G Stonington CT
That's kind of amazing! Both for the effect in and of itself, and for your detective work in finding the explanation. I'm not really a true radio guy, but it must have been quite the head~scratcher at the time (not to say, spooky!)
It reminds me of the story (you may well be familiar with it, if so, forgive me!) of the radio astronomers who picked up an anomalous signal, repeating itself at regular intervals. Scrupulously they went through lists of satellites, possible military, aviation, business, etc. users, but it got so that, almost for the want of any other explanation, they were starting to wonder, in almost hushed tones, "Could it be - could it _really_ be - _extra terrestrial_ in origin?!" By which I actually _do_ mean aliens, as opposed to signals bouncing back off of the moon, Jupiter's magnetosphere, anything like that! Like good scientists are supposed to though, they continued to do their best to investigate and exclude every possible other contender before even talking out of school, let alone holding press conferences or anything like that (or maybe they were just afraid that some guys in dark suits might visit them and give them a mind wipe!) Anyway, it is as well that they did, for it would prove that they were eventually able to isolate and track down the elusive and intriguing signal... to the break room, where a colleague, presumably occupied on a different project, was warming his lunch in the microwave!
I had the same thing happen in October 2023, on 10m, 50w, mobile, SSB. I was listening to a station just far enough that it was too far for ground wave and he had a weird sort of warble to his audio. I heard his signal echo and realized I was copying him long path. I went up a little in frequency and heard a Bulgarian station like he was across town (I’m in Pennsylvania). That’s when I heard my own echo. I’ve heard it called LDE/Long Delay Echo-the signal actually goes around the world several times before fading. This was about 11:00 am local time.
Wow
As someone with just a passing interest in radio, it never ceases to amaze me that radio signals can travel so far on 'light~bulb' powers!
Back in the 90's I made a contact with a gentleman on the east coast of the United States, and he was working contacts for long path contacts. He didn't want to make contacts with people unless he was hearing the long path echo. It was really crazy, he explained it to me what he was doing and I listened to him for probably an hour.
Fascinatinig
I haven't heard my own echo recently but years ago whenever I was first starting out on HF, I did one day on 20 meters and I'll tell you it was one of the weirdest things I've ever heard. Great video 73 👍🙂
Hi Colm, I also have this happened to me in the 80s while I was Mobile. I can’t remember the frequency. I like you at the time assumed it was a troublemaker or something but I now know it was quite an experience with a very loud delay of about five seconds but because it was so clear and loud I did naturally assume I was being recorded, I was told it was Myself hearing myself hopping around the world.🌎 😮
Haven’t seen it mentioned yet specifically in comments but if you are listening to your own signal come in your receiver just after you unkey, it may simply be a result at digital processing latency. If I simultaneously listen to my transmitted audio from a local transmitter in an analog receiver and an SDR based radio such as my IC-7300, I can hear a distinctive echo/ reverberation effect. The echo effect is even more extreme when using an 8bit dongle based SDR that I run on the iMac desktop shack computer. I cannot use either the 7300 or the 8bit SDR as a sidetone for a standalone CW transmitter because of the latency effect. Any remote internet SDR one uses will have latency when listening to a transmitter you are keying from your location. The Kiwi SDRs all have about a 3 second latency, you can use that latency to monitor yourself , if you are muting a Kiwi SDR while transmitting, the last three seconds
of your transmission will be audible when you unkey. Of course you can also record yourself on the Kiwi SCRa and have them send you a .wav file of the recording.
AJ1G
I'm not finished with the video yet, but when I was in the army working HF this was quite frequent. We were told it was tropospheric/ionospheric return, or the long path reach. Most often occurring slightly below 10 m and slightly above 40 m.
Now I'll watch the rest of the video and see what you come up with.
Great video! The magnetic theory makes absolute sense!
Yes have heard it before on 10M just before Christmas
Heard it on day 2 as an Amateur. I squeezed a highly directional miniature V beam into my garden and was astonished at the delayed echo. Changed frequencies a couple of times and still heard. On 20mtrs from memory but might just have been 15.
Fascinating.
I think anyone who has been on HF for a while has heard this before. It's not always super obvious like half a second or several seconds like this one. I hear it very often on European stations here in Alberta, especially on 20 meters and lower in frequency. Sometimes on 10M but not as often and the delay is much shorter on 10M typically. It usually sounds like the operator is in a big empty room with all hard surfaces like the echo or reflection is local to the operator and microphone being used. But upon hearing that exact same station at the same time on say a remote SDR somewhere else in the world, or even a recording replayed by another station back to them, the audio is very dry with 0 room echo. From that I know that the operator and microphone are not causing or picking up room reflections and that it is a longpath verses shortpath echo or something else causing long reflections to occur. Sometimes I will hear the same operator at a different time and the audio is bone dry without any room sound at all. If one has any experience with recording using microphones in a room you will understand how this works. Yes, an RF signal can go around the world 7 times in one second which would perhaps make one believe that it would be nearly impossible to hear an echo, but you need to take into account how signals propagate and reflect (bounce) around the ionosphere and the earth. That signal might bounce a thousand times on it's way back to you and each one of those bounces takes a little more time. I absolutely guarantee that your experience here was not someone rebroadcasting your audio from somewhere. Too many people heard the delay in too many random places for it to have been a station rebroadcasting. Also, the delay time variation was totally different and unique for everyone, even within your own audio examples. If it were a station rebroadcasting, everyone would have heard it at the same time and the delay time would have been more consistent on each transmission. An automated rebroadcast would have been an exact delay time, every time. A person clicking a mouse or something might have had some variation in the delay time, but not like this. It was a naturally occurring phenomenon. A phenomenon reasonably well explained by the space weather expert as well. I'm not sure 47 minutes is a natural phenomenon as there is inertia involved and that will eventually cause the signal to degrade past the point where it can propagate, or at least too weak for our equipment to receive at any rate. I suppose it could have been a planetary reflection but that's improbable in the extreme for so many reasons.
Long comment. Some interesting thoughts!
I haven't observed echoes as long as yours but I've often had them around 250ms around dusk on 15m and 17m in the last couple of years, and around sunrise on 15m. I can listen to myself on the web SDR down at Weston-Super-Mare and hear the ground-wave and delayed signal quite plainly, to take any local effects out. The effect works for 15 minutes or so and then as it gets darker it dies out. I have got a few recordings somewhere I have meant to do a video on - I have one very sketchy video up on my channel of 15m morning weirdness from before I started trying to analyse this properly. This is all from my portable spot by the harbour where at least some of my RF is going out at very low angles indeed.
Fascinating!
An SWL during the mid 1990s told me about these "round the world" echoes. Apparently, on CW, it can confuse the receiving station as it can sound like several stations transmitting at once. This often leads to the transmitting station being told to slow down their speed QRS (I believe), to help eliminate this phenomena and make their transmission more readable.🤔
That's all very well Cal, but when you cut the TH-cam stream audio, the phenomenon went away, so I'd swing towards broadcast from the stream. By whom and where, I don't know.
Happened to me while operating mobile on holy island last year . I was using a Yaesu ft 857d and a chameleon MPAS on 17m it was on all signals as well as my own when calling CQ. I definitely think yours was an LDE especially because the echo was immediate heard after your transmitting had ended if it was someone recording and retransmitting there’d be a much longer delay that was immediate
Back in the mid 1990s (before I left the hobby for a long time) I recall conversations on 10 and 11 meters that had doppler shift, and delays on signals. Very occasionally an echo from the other station. No mechanical help there either.
You will sometimes notice huge doppler on some arctic signals via the auroral belt. At other times you canl hear echo when you receive SP and LP from the same station, but this is normally 130ms or less difference. Nothing like this video. I have even worked a friend of mine LP on 20m SSB. He was only 60km away, but the distance over the air was 39940km :)
I remember hearing my own CW echo on 40m back in the 1980's. Very odd indeed at the time. Mark - G0ACQ.
Fascinating! I've never heard it. Could it not be multiple skips, eventually coming back around the world to you?
I've has weird stuff happen on 80m but no long duration echo... yet. It's pretty interesting and I lean towards the solar explanation.
As I told you live in chat, it was someone rebroadcasting your audio from TH-cam.
The delay was consistent with the one from your live streaming, and when you muted your youtube audio, the "echo" was gone. Moreover the transmission bandwidth was different and with a different equalization; in my receiver the "echo" signal was stronger in some bands while maintaining its recognizable bandwidth and EQ. I'm quite sure it wasn't a natural phenomena.
Why would someone do that anyway?
@xanderlewis good question. Probably to annoy everyone.
@@xanderlewis People create all sorts of QRM on Cal's streams, and the streams of several of the TH-cam ham radio fraternity. I guess they just don't want anyone to have fun.
one simple little experiment you could try. Naturally you aim your beam towards where you expect a response, eg VK, but how about trying to send it over a path that included the maximum amount of sea and minimum land to see if it 'bounced better' and came back round. say, just east of Greenland and then do the same thing when there are reports of strong aurora to see what happens.
I do know how odd DX can sound at times. In my early General class days I was working CW on 15 meters in the afternoon and I was hearing the normal US CW chatter on the band. Suddenly the band went quiet and the US CW signals went silent - like when you are in the forest at night and the crickets and frogs go silent... I sent CQ and a very faint and warbly signal came back to my call from Novosibirsk. That was my first ever DX contact. About 5 minutes after the end of the QSO the US signals came back and that was the end of it. I figured it was some kind of hop across the NP with aurora flutter involved giving the signal that strange sound, but it does not explain why the band went quiet though...
Yeah.. If you listen to my clip again at 0:50, you'll hear the band change for a few seconds and different skip zones quickly come in and out.. I can briefly hear another QSO, perhaps west coast that comes and goes.
Yes that´s true, i had that in the last cycle with my own signal. Backscatter or all around the world.
73 Joe DH1KJ
I have had this happen to me back around 1987-1988 during a peak sun cycle. on 11meters from CU3 land. I don't recall what part of the world I was talking with now, but as soon as I let go of the PTT I heard myself.
Beautiful!
Ap on that day were 9-27 meaning it still was not very calm conditions. If you want the least attenuated conditions on low bands you would like a positive DST (usually happens when it has been calm geomagnetic for many days). Echoes on 40m is common, but normally you can explain them with the normal 100+ milliseconds delays LP or skewed, and you can hear several paths at the same time (making CW decoding difficult).
I do not buy that someone can JUST copy the echo travelling 15 times around Earth, and not all the others before (1-14) that should be stronger. I have not hear about echoes travelling more than two times around Earth, but I am sure it could be 2-3 times if power was high enough.
Most of the times I've heard long path it was at most the last letter or part therefore... However, I have had something similar happen once... Not quite as long as yours, but long enough to hear the number and suffix of my call sign (phonetically.) It took me by surprise. I thought something strange was going on and released the mic after saying "cq" and heard myself saying cq. Eerie.
Absolutely fascinating. I have experienced long path echo but never this delayed. It does sound dxy to my ear, and cannot understand why anyone rebroadcasting (as suggested elsewhere) would result in a single echo not multiples - in many places.
There is still much we have to learn about propagation, and your experience as it ties up with magnetic events is really interesting.
@@g0jjg Audio taken from TH-cam while Cal was speaking, may only create a single echo; no feedback issues or anything else because it was only his voice.
@@alexr71 I now query this rebroadcast. Only *my* signal was being rebroadcast, not the other participant - and folks hearing multiple different times of the repeat from half a second and up - also "both paths" confirmed.. It came and went pretty quickly and when I started testing it out, it dropped off altogether.
@@DXCommanderHQ I see your point, but... I think the delay time reported in chat was approximate and I think it was reported as different from person to person only because of that approximation.
Delay time was around 3.15 sec (I had a chronometer) and it was really consistent with TH-cam delay (you can check it under "stats for nerds" during the live streaming).
At the start of the "echo" signal, I could hear clearly a particular noise just like when you use a amplifier; that noise was not in your audio. Furthermore bandwith and eq were different.
The "echo" signal was clear, without any distorsion or shift in frequency, and I can remember when you changed band it was louder than yours.
Rebroadcasting your audio from youtube without taking other sounds is not difficult; just hit the PTT at the beginning (it doesent matter if the timing is not 100% right) and just drop it when you stop talking. In your streaming there is around 1 second delay at the end of your TX, so it's easier to rebroadcast it.
I would love to see the full stream again, but in any case the ultimate test would have been to broadcast by surprise without transmitting the audio in the live; if there had been no echo in that case, you would have had the final answer.
I stand by my theory due to the inconsistencies with a natural phenomenon, but at this point it is impossible to prove either hypothesis.
@@DXCommanderHQ
I see your point, but... I think the delay time reported in chat was approximate and I think it was reported as different from person to person only because of that approximation.
Delay time was around 3.15 sec (I had a chronometer) and it was really consistent with TH-cam delay (you can check it under "stats for nerds" during the live streaming).
At the start of the "echo" signal, I could hear clearly a particular noise just like when you use a amplifier; that noise was not in your audio. Furthermore bandwith and eq were different.
The "echo" signal was clear, without any distorsion or shift in frequency, and I can remember when you changed band it was louder than yours.
Rebroadcasting your audio from youtube without taking other sounds is not difficult; just hit the PTT at the beginning (it doesent matter if the timing is not 100% right) and just drop it when you stop talking. In your streaming there is around 1 second delay at the end of your TX, so it's easier to rebroadcast it.
I would love to see the full stream again, but in any case the ultimate test would have been to transmit by surprise without broadcasting the audio live on youtube; if there had been no echo in that case, you would have had the final answer.
I stand by my theory due to the inconsistencies with a natural phenomenon, but at this point it is impossible to prove either hypothesis.
@@DXCommanderHQ I wrote you a detailed response twice, but I don't know why TH-cam deletes it instantly; I'll try to change some words and see if it will be published...
Okay, third comment, but I just went and looked at an EME video where a guy was hearing himself bouncing off the moon, and the delay was almost identical. Nearly 4 seconds just counting out loud. I'll have to get my laptop out and grab the video clips and actually time it in the video, but you might consider doing the same with some of these EME videos that are out there. Cuz it certainly looked to me like exactly the same delay. If that's the case, that would make the moon a candidate.
Was that video from Goonhilly in UK Kevin? HF moon bounce would be a really interesting phenomena!
Kevin.. Fascinating.. The moon was 8 degrees above the horizon at the time in question and exactly opposite the rear lobe of the yagi!
@@DXCommanderHQ Well the next thing to do would be to look at where the stations were that heard the echo and where the stations were that could not hear the echo, and then look at where the moon was. If the stations that could not hear it were on the opposite side of the Earth from the Moon, that would make sense.
And also you've got your original video so you can do the timing better, but go look at some of the UHF VHF Moon bounce videos where they hear their own echo and compare the timing. Perhaps that event Dr Skove pointed out did allow HF to pass through the ionosphere.
We could be contributing to solving this mystery.
@M0RMY I'd have to go look through my history, but it was somebody copying moon bounce of their 10 m CW transmission. And I also looked at one of a guy doing VHF voice, but there's many of these videos out there. The timing should be the same in every case.
@@DXCommanderHQ Another thought that occurred to me, made the hair on the back of my neck stand up.
Why does the ionosphere reflect HF frequencies back down? Because it is charged up by the solar wind. So if the magnetic pole in the solar wind reversed, well wouldn't there be a short period where the ionosphere's charge dropped and then came back up reversed? Wouldn't there be a short period of time where the charge was basically neutral as it was flipping, and during that time perhaps it could allow HF through. This is really starting to make sense.
There’s a RADCOM article about this effect written in the late 80’s called ‘AMTOR spins a time warp around the earth’ where an AMTOR broadcast was sent and then received itself a few seconds later, the effect was a long path signal travelling around the earth. If the circumference of the earth is taken and divided by the speed of light the result is about 1.4secs, then extend the distance to account for multi-hops and the delay is about what you were experiencing. I think there is nothing particularly unusual about these events.
Maybe.. The only fly in the ointment is that at speed of light, we're looking at 0.13 seconds for an RF circumnavigation.
Greetings, I also have heard this before, both my signal and more often other signals. Mostly during periods of high solar activity. 73 Jon KT4KB
AKA coronal hole stream impact. When the mag fields are pointing north, less energy from the Sun gets through the atmosphere..
The Feb edition of ARRL's QST has an article about long delayed wireless echoes by VE3HX
I have heard it. Always thought long path and short path. But also think Radar....that would get bounced back...just a thought.
Art Bell was a ham and he demonstrated echoes on his radio show. This was at least 20 years ago.
The easiest way to determine if it's a re-broadcast or not, would be to quickly QSY up or down a kHz or so, and see if you still hear yourself
From what I recall from the original stream, Cal cut the audio to TH-cam and it went away.
It came.. and went as I started to experiment.. So that part is unexplainable.
I think Mulder and Skully need to be involved in this... what a reply from Tamitha, wow. Its all that banana energy. 😂😂
In 1966 I experienced a 20 second delay on 15 meters. This effect repeated for about 15 minutes. To rule out any kind of rebroadcast I kept changing the frequency and the echo still kept returning. An asteroid bounce perhaps?
Fantastic!
I'd go with Dr.T I was on that day and talked with you on 20m and 40m if I remember right it was cool to hear. W9US
Yep. Have heard this but much shorter... "CQ CQ CQ 2 echo zero papa tango yankee" release the PTT and hear a strong "o yankee"... Thought it might be a global bounce.
AMazing.
very interesting. I'm afraid we will never know for sure what it is.
The more you talk about it the more some funny guys will rebroadcast your stuff now 😂
Completely off topic- sort of - But i wonder if this anomaly was the inspiration for the movie "Frequency" starring Dennis Quaid and Jim Caviezel about a Son of a Ham radio operator talking to his father from the pass from his old ham radio set cause by solar effects etc. Great movie if your a Ham or CBer you may really enjoy this movie! I sure did.😉
Well the delay is far too long to be propagation around the planet. It takes about two tenths of a second for a signal to make its way around the planet, 25,000 mi or so at 186,000 miles per second.
The information from tamatha was very interesting. Normally HF does not make it out of the ionosphere. Perhaps that shifting of the magnetic field polarity in the solar wind punched a hole in the ionosphere that HF signals could get through allowing them to go out and bounce back off of something else like the moon or some outer band of magnetic field or ionized radiation. But that's just a guess.
I suspect it is longpath RF reception of your own signal. I have heard it, and some believe it is SDR retransmission of the signal.
As I said, it could be many things however Tamitha's response nailed it for me.
You were broadcasting wirelessly, correct? Perhaps it was an internet issue. Perhaps your internet did the rebroadcast? Or your radios internet receiver system had a glitch.. Just a thought. Interesting stuff though!
No.. Other people were also hearing this.
I had a very similar experience a few years ago during a contest. I was calling cq contest and heard my voice repeating the cq. Being new to the hobby, it kinda freaked me out. I wasn’t sure what was going on. If I remember correctly, at that time I was running 100 watts and a fan dipole at roughing 35’. I don’t remember what frequency
I was on. At that power with that antenna, I kinda doubt it was long path. So what was happening? 🤷🏻♂️. I only heard it a couple times. Thanks for sharing!
Who knows :)
The information from Tamitha and the trimming lines up with what happened on radio time with that long duration echo. It was the flop in magnetic field which was recorded at that time. The magnetic field grabbed some of the RF and spun it around like a motor and set it back at a delayed time. This was done around the north magnetic pole . The North pole has been shifting so if using a compass to find santa claus at north pole will will get lost . I have hurd short echo on 10 and 11 meters talking DX and 6 meters as well. Makes a hard copy . Sounds like a echo mic turned up to much . And this did not happen south of equator. More proof of north magnetic pole. Great information given . Cheers ! santa just hiding his location . Many did not get what wanted for Christmas. I would hide as well . LOL
What a great comment!
@@DXCommanderHQ Fallow the science ! Cheers mate !!
Was this on 29-1 +- 8:55 UTC?
12:30 UTC, 4th January 2025.
In real basic terms it’s almost like the signal is trapped up in the ionosphere due to turbulence then spat out causing a bit of a delay? - M7VAC
Yes, that's what it felt like..
I heard a short echo on a German station who was calling CQ and thought he must have even running QRO and beam on 40 Mt's, I worked him and told him about the echo and asked about his station. He was only running100watts and an end fed wire. I thought it only happened with high power. I will check my log for the date, it was only a few weeks ago, but as it was from my mobile station I don't log the time. I was parked on the top of a river bank having a coffee break while at work at the time. He didn't comment about the echo so I don't know if he could hear it and I couldn't hear it during the QSO
Ken G6YYN
.. and mobile too. Interesting.
When I got you on 12m about a year ago, I had to turn off TH-cam not to get confused by both audio, noises.
Oh yes!
That's fascinating, isn't the plant an amazing place
I did in the early 2000's
I think you're hearing your signal make it around the earth and coming back to you. I have only heard this once while calling CQ on 15m a few years or so ago. I was able to briefly make qso's with Japan at the same time I heard my 'echo'. It didn't last long and at the time I was only running 100w barefoot. My qth is in PA, so I was excited about the japanese qso's as they aren't common for me.
This was my thinking also that essentially you are hearing yourself 'long path' ?? I don't know enough about how Temperature etc alters the speed of sound though to work out if this would account for the delay.
That would be a much shorter echo. It's about 25,000 mi around the Earth, and a radio wave would propagate that in under two tenths of a second. There was a much longer delay on this echo.
I think Kevin might be right here
Too long a delay for once around the world - that's milliseconds.
@@loughkb Hi Kevin - hope you are OK - I agree.
I have heard this back in the 1970's. CW is more fun to play ping pong with it.
ping pong! LOL
3.15s is 1000000km. Can‘t believe that your Signal could Travel as far. TH-cam transmit: no, because in that case other Parts of the stream would have been transmitted, too, not just your voice. Web sdr: Same here, at least Parts of other transmissions would have been heard. But it Must be man Made And automatic, otherwise the Delay would Not have been as constant. So propably a neighbor with a deaf rx And a remote tx .. 73
Old stories from long ago about repeats after years...
Nothing new, under the right conditions I have heard my own signals, before youtube.
I have experienced this before , however i was very very drunk🤔
HAHA
Hi, Cal. This may seem like a looney idea, but it popped into my mind as I considered the time factor and Tamatha's discussion.
In the best case, the human hearing range is ~ 20 to 20K Hz. We also know that under certain conditions, vibrations will experience resonance depending on the geometry and consistency of the vibrating medium. So, what if, under the space weather conditions described by Tamatha, the electromagnetic signal essentially began to resonate in the plasma medium creating a self-perpetuating resonant echo, this resonance occurring across an extremely wide "bandwidth" with only the ~20 to 20K Hz segment being obvious to us as the self-perpetuating echo signal cycled through this large, resonant bandwidth.
Consider the effect of bringing a crystal water glass to resonance by merely tracing a wet fingertip over its edge. As the resonance gains amplitude, less fingertip tracing is required to perpetuate and often increase the amplitude.
With all that being said and considering the above hypothesis, could the space weather at the observed moment be creating a plasma condition somewhat similar to the crystal water glass, the electromagnetic R.F. providing the stimulus bringing the plasma to resonance thus "storing" and "retransmitting" the signal across this wide, oscillating bandwidth with only a portion of it being audible to us across time creating the "delay" observed as the large resonating plasma body worked its way through the vibratory frequencies?
I hope that made sense.
It sort of makes sense - but I'm a normal mortal!
If it happens again on a live stream stop the stream temporarily.
Aye science and that, i reckon its aliens! 🤣
KE8PMM, May have bounced off an asteroid.
Carl K9LA is my neighbor!! Want me to go knock on his door and ask??
On CB, I used to mess with people by recording the audio from a Web-SDR and playing it back 1-2 seconds later at the same time. It always sparked debates about this "phenomenon," lol.
HAHA
Like loughkb, my money is on the moon, no, I meant check the position of the moon when you have that experience. Fun to think about! Oh! medication time? I'm doing that now with an IPA. Cheers AA7MO
Moon was in correct place! Just directly behind the yagi, precisely where there is some gain.
...the time to the moon and back would be around 2.5 seconds..That would fit, wouldn't it?..@DXCommanderHQ
Happened to me a longtime ago. 73 de DJ6JH
I regularly speak to g3sed and mm0tfu regularly on backscatter, pretty normal.
What is the delay time you perceive?
@@M0RMY very little, we have warbling going on all of the time with local HF, if we are talking either local or dx, with aeroplane scatter. Usually when working DX...VK, JA etc, with quite an echo there's a good chance that lp or sp is better... depending which way you are beaming in the first place.
Back-scatter is slightly different and dual LP/SP sounds more like reverb.
I have heard it before on10meters, in 1989year, CW 50wtts antenna 2el
Quad.Leo.ur3if.
I once experienced a VERY long delayed echo of hearing myself a full day after I had last sent a CQ. I was preparing to call CQ on an 80 meter frequency that I regularly would operate on and while listening to the frequency to be sure it was clear, I heard someone calling CQ and then I heard my call being signed! The fist sounded just like mine. This went on for a few minutes and then stopped. Then it started up again! I remembered that I had called CQ twice on the same frequency at about the same interval the night before. To make a long story short, it turned out that while I was operating on the previous evening, my wife was recording a show on our VCR. At the time I heard my mystery echo, she was playing back the show on the VCR. Apparently the 80
meter RF from my CQ got into the VCR and was recorded onto the video tape as a CW signal at my operating frequency, and when the video tape was played back, the signal was re-radiated (quite strongly by the way) by the VCR!!!!
AJ1G Stonington CT