Monday 20 April 2015

More Magic


For the third day in a row, someone has sprinkled 6m magic-dust over the Pacific Northwest with more long-haul propagation into southern South America. The openings have been characterized by their very small footprints and today, unlike the previous two days, the footprint locked-in on my own QTH for over an hour.

For the most part, signals were in the 559 range but at times would build up to true 599 levels, reminiscent of the previous cycle's F2 north-south openings in the afternoon.
During the entire opening, strong sporadic -e signals from California, Arizona and Nevada were present so I suspect that the propagation mode was Es to TEP and from there to southern SA who knows! I doubt there was any F2 involved (unless it was ver SA) as the solar flux just doesn't seem to be high enough to support that mode. In all likelihood, the present coronal hole stream that is impacting the ionosphere has been the trigger for these unheralded openings.


During the opening, the following stations were worked, mostly on CW but some on SSB as their signals were very loud at times:


As mentioned in my last blog ... who knows what this cycle will do next as the surprises just keep coming!

Is there enough dust left for a fourth day in a row?


Unknown said...

Hi Steve


record distance when confirmed

that was sure alot of fun !

Steve McDonald said...

Congrats Perry...I heard you in the melee. It's amazing how much that tiny spot moves around. You would think at that sort of distance that the footprints would be much larger....but more like a tiny entry into the wormhole and out the other end with another small moving footprint. It's interesting to see these on the map and how uniform they were distributed along the E-W path.

Anonymous said...

Nicely done guys - I heard you both working stns in both CW & SSB. Sorry Steve, but I have to argue this one with you: it was NOT an Es-TEP linkup. It was a (single-hop) Es to F2 linkup. I could hear a few XE2's working the S. Americans using CW en Espanol; also a few W7 AZ stns. WA7X/b & XE2K/b were both pounding in here the whole time. My arguments: Wrong time of day for TEP which occurs evenings AFTER the F2 has dissipated. It is a residual-scatter mode much like aurora. TEP is always equidistant on both sides of the geomagnetic equator, whereas this opening (like last Thurs.) was not. TEP almost never occurs farther north than TX. I've experienced TEP during 3 different trips to Jamaica discovering TEP on FM broadcast evenings after sunset. It has the same "hollow" "watery" sound with NO audio tone. None of that was prevalent yesterday - signals were clear & steady. I've also been lucky to experience Es-TEP on 6M here. Stations at the Es end-path were clear, while the TEP stns sounded like aurora. Noted 6M/TV/FM Dxer Pat Dyer WA5IYX & I both were tracking the opening & Pat noted increasing F2 MUF's from his QTH in EL09. Stations heard here: CE2AWW, CE3SX (SSB) CX3AL, CX1DDO, LU4PZ, LU6QI, LW6DG, LU4FM/b, PY6ATB & open carriers on the 47.900 & 48.300 CE WFM background music services.

73 Mike VE7SKA

Steve McDonald said...

Hi Mike - I'm afraid I'm going to stick with my original assessment. I think the classic TEP as experienced at the equator is a much different animal from what we are seeing...the old 'classic' is not the only model nowadays. In an earlier article (link below)by VK2ZRH he describes many of the characteristics that this particular opening supported:

"For paths oriented generally north-south ... afternoon TEP generally occurs between
1400 and 1900 local mean time"


"Afternoon TEP is generally experienced during the equinoctial months of March-April"


"The signal fading rate experienced is generally slow, with shallow fades every few seconds, occasional
deep fades of 20-30 dB and often sustained periods of very strong signals. Doppler shift/spread is
generally small, generally in the range 1-5 Hz and varying slowly."

This describes many of the characteristics noted yesterday. A doppler shift of just 5Hz would note be noticed by ear and would not be described as "fluttery".

I will grant that the F layer was involved, at the chordal hop's entry point and at its exit but this is not F2 as we have come to know it.

Another great read (see link) is by K6MIO/KH6 and he describes:

"In the Northern Hemisphere the Es links to the TEP system are usually seen in mid to
late April, at the time when the ending of the TEP season and the beginning of the Es season overlap for a

...sound familiar? Have a look at page 15, FIG. 17 almost exactly describes the condition of our opening...even the map looks the same. It's also interesting to note that in the 17-page paper, the term 'flutter' is not mentioned.

It is clear from reading both papers that TEP is a complicated mode and that there are several modalities involved. It would be nice to think that this was classic F2 but from what we both know about the sound of F2 signals and their characteristics, this opening missed the boat in my opinion. Flux values are just too low and it's not F2 season, even in SA.

note 1:

note 2:

Anonymous said...

Steve - those are some very persuasive arguments. I have to agree that TEP is a very complex mode & there may be a number of anomalies that are definable variants. BUT...I'm going to stick my guns that it was F2 & not TEP involved in the Sunday & Thursday openings. Given enough time to research, I too can come up with data to back my arguments. Ain't it just grand that we actually have some 50 mHz DX to discuss, debate & argue about instead of our usual 6M grumbles ("The Static Band")?? :-)


Steve McDonald said...

I guess we'll agree to disagree Mike. I had a good discussion this morning with several guys who have been involved with this type of opening over the years, including one in Chile and they all agree that it is Es into chordal hop TEP ducting along the F layer ... but not F2. I wish it were F2. Signals would have been a whole lot stronger but wrong time of the year, SSN too low. I think the only thing we disagree on is the method of entry into the F layer... yours going from Es into F2 and mine from Es to TEP zone then chordal duct F and reversing at the other end. Guess we'll never really know for sure ... all agreed that they have worked TEP with no flutter evident. All part of what makes the study of propagation so darn interesting!

CE2AWW said...

Hi Steve and Mike

Steve... I have to agree. Definitely TEP on my end and an E's link on your end. I am a relative novice on 6m as you know as I have only been on the band the last 3 years since being QRV from CE2AWW but I think that the 144 entities I have worked to date on 6m including the 2 new ones today ... T77C and OM3CLS give me a clue as to what might be happening. K6MIO's new paper on TEP really describes well the various forms of TEP and he in fact used several of the qso's made by me in the last few years to emphasize some of his findings. Most of my TEP openings and close to 10,000 qso's completed do not show flutter all the time. That is because they are mostly transequatorial chordal hop off the tilted north and south skip points. When we do experience flutter which for me is maybe 10% of the time it is a result of multi path chordal hop when the signal enters the various layers and ducts caused by the daytime electron fountain that exists over the magnetic equator. In this case the signals have the TEP flutter or spread F as some people call it and is often talked about. I have heard it so severe that SSB qsos are not possible and I must QRS for CW qsos. Todays huge opening to eastern Europe for me was just another TEP opening on this end and E's on the Europe end. As you well know I am a seat in the chair guy and have spent many many hours listening and CQing over the last few years and hopefully learning and helping others to better understand just what is possible from a good TEP location. As a final comment I am of the opinion that I have yet to experience a F2 opening so in all likelihood I may never experience one but for me TEP is just fine, after all it is a form of F layer propagation. Anyway, a lot of words to say ... "I agree". Hope to work you again soon amigo.


Steve McDonald said...

Hi Dale & thanks for your valuable input and affirmation of my take on the mode! This recent opening was, without doubt, the best I have experienced regarding Es to TEP, of which there have been several over this cycle. I think the only real classic F2 openings I have seen were a few years ago (was it 2012 maybe) when I worked about 40 W1's and 2's in the morning. The rest has all been via Es to TEP.
It's a pity that you have not ever worked any top-of-cycle F2 as you would never forget it. The best example I recall was working LU5VV in 2000 who was running just 8 watts out. His signal was against the pin. If I hadn't known any different, I'd have thought he was parked outside the house in his mobile ... it's amazing stuff!