AmateurRadio.com

'YPM' - 274kHz courtesy: Alex - VE3GOP

It's CLE time once again! For you low-frequency buffs, another challenge awaits. This month's frequency range covers the mid-band, 270.0 - 319.9 kHz.

A list of all of the North American  targets in this range can be found in the RNA database, while targets for European DXers will be found here... specify the frequency range wanted and check 'show all results'.

An excellent target for this CLE is  'YPM' in Pikangikum, Ontario, on 274kHz. Its 25 watts and big antenna are heard well throughout North America

From CLE coordinator Brian Keyte (G3SIA) comes the following reminder:

A recent posting on the ON4KST 6m Chat page brought up the question of QRN coming from  fluorescent lighting.

Lefty, K1TOL, had a lot of QRN coming from his neighbour's garage, about 1,000 feet away. He solved the problem by changing the ballasts, purchased at Home Depot. This is the ballast that solved his problem, so if you are having similar difficulty, perhaps this will be of benefit.

Sometimes just changing to a different bulb type (manufacturer) will solve the problem as well but from what I have read, you get what you pay for and likely the bargain-bin bulbs are not the quietest.

As much as I hate to admit it, for a few short weeks every summer, I become ... get ready for it now ... a CBer! Now I'm not talking about what might typically come to mind when thinking about CBers ... for me it's more of a love-hate relationship. You see, the 27MHz CB band, and 27.385MHz in particular, happens to make one of the best indicators of Sporadic-e openings on the face of the planet. Unlike the vast empty wasteland that 10m becomes during the summer, the 11 meter band is jam-packed full, with thousands of operators ... and some days it seems as if they are all on the 27.385 MHz (LSB) calling frequency.

With my receiver quietly running in the shack, the frequency can suddenly jump to life, with hundreds of stations calling each other in a matter of seconds. Sometimes it's like a switch has suddenly been thrown to 'ON'. This is not too hard to understand as the present suspected cause of Es is sudden high speed wind-shear within the E-layer. Have a quick listen to what the calling frequency can suddenly sound like:


Now the beautiful thing is that strong Es on 11 meters usually heralds the possibility of 6m also opening via the same mode ... usually 30 minutes or so later if it's going to happen. Often a CQ on a seemingly 'dead' 6m band in the direction of the 11m Es, will produce a response from an equally surprised operator at the other end.

I don't think I've ever heard Es on the 6m calling frequency without hearing Es on 11 meters beforehand. It's been my experience that the band always opens from low to high, in terms of frequency, so it just makes sense to listen lower (11m) to get a heads-up for what is likely soon to follow on the magic band. As well, knowing that there is 'zero' Es on 11m, can let you rest assured that nothing will be happening on 6m via Es ... at least for the time being.

If you haven't already tried it and have a second receiver that can be put to use as an 'Es-monitor', you might be pleasantly rewarded. Even though knowing that the band will soon open might rub a bit of the magic away, I think it's still well worth it!

courtesy: https://openclipart.org

When I was in my 30's (30+ years ago), my very good friend Tommy (VE7BLF), reported to me a serious of LDEs that he had heard on 160m CW. At first I was skeptical as the claimed LDE was heard 30 minutes after his CQ.

Tommy happened upon the LDE when tuning around the band one December evening. He heard a weak, warbly ... "CQ CQ CQ de VE7BLF VE7BLF K". A chill went up his spine as he had actually called CQ about 30 minutes earlier, and was answered by a K7. Sure enough, the phantom LDE soon came back to the K7 while Tommy listened to himself send the report, name and his QTH information on the next transmission! Listening to his own signals, 30 minutes later, really shook my friend up as he had no idea what to make of the incident.

Over the next few weeks, Tommy heard several LDEs, some with separations as much as 3 or 4 days and during this time made several recordings of the events. He made a copy of the recordings for me to listen to and the sound of the signal really did send shivers up my back. It was tormented, warbly, with a bit of flutter and very weak. It sounded as though the signal had been ripped apart on a trip to hell and back, adding further to the mystery.

The LDEs stopped as quickly as they had begun and were never heard again but in the meantime, Tommy and I speculated on what might be the cause. Were they genuine LDEs? ... they certainly sounded as if they had been on a very long trip ... or was the explanation something far less sinister? We never did solve the mystery but I had suggested that one likely explanation might be a faulty (or normally operating) VCR, somewhere in the neighborhood. Someone that happened to record at around the same time that Tommy was operating and playing the program back when Tommy happened to be listening. It seemed a far-shot and one that we never tested, preferring to think of it as another one of the mysteries of radio. Unfortunately Tommy became an SK several years ago, never knowing the cause of his mystery signals.

During a recent discussion with Tony (VE7CNF) and Mark (VA7MM) about the newly imagined plasma tubes, the subject of their possible link to LDEs also emerged. I related the above story and Toby immediately went to work with his old VCR! In his own words:

Yes, old VHS recorders could cause long delay echoes. When Steve mentioned it, I had to try it. I attached a photo and some recordings.

I hooked up my old VHS recorder with BNC video and audio cables in and out. I pulled out the video cables a bit to disconnect the shields, so RF could leak into and out of the video ports. My IC7410 was connected to a dummy load and split, through a T connector, to a whip antenna on top of the VHS.Transmit power was 100W to the dummy load.

I transmitted while recording video. When I played it back I could hear the CW signal pretty much on frequency. I tried this at 1820 kHz and the signal had a lot of frequency flutter. At 3510 kHz the playback signal was stable enough for SSB.

So, RF leaking into and out of the video cables of a nearby VHS recorder could explain LDE's where the delay is hours or days.

courtesy: googlemaps.ca

My recent blog discussing the 49m Canadian stations, discussed the need for a better picture of the CKZU (6160kHz) antenna system. Located on the mudflats of far western Richmond (Steveston) and a stone's throw from the Pacific Ocean's Georgia Strait, CKZU's  gets out very well for its compartively small 500W transmitter.


On a weekend bike ride along the West Richmond dyke, Mark (VA7MM) snapped this wonderful close-up view of the system:

courtesy: VA7MM

It appears to confirm the rumor that the antenna system consists of a two-wire beam (using wide-spaced folded dipole style elements) ... one element being driven and the other element being a reflector. According to Mark, the orientation would beam the relayed CBU-690 signal up the coast of British Columbia and not towards the SE as the original Google photo appears to indicate. It is certainly a well 'overbuilt' structure. No doubt its height contributes to its ability to radiate a good signal all around North America (and Europe).

So the next time you are tuning around 40m, drop down a bit and see how their signal sounds at your location ... you may be pleasantly surprised.

If you haven't seen this by now, you'll want to check it out! It seems that the world of astrophysics has been set all agog by a brilliant Australian undergraduate student's recent discovery. Cleo Loi from the University of Sydney has used a combination of radio telescopes to prove the existence of earth-surrounding tubular plasma ducts. Travelling from the ionosphere to the edges of space, these multi-layered plasma tubes were believed to exist but were never proven ... until Ms. Loi and her team managed to image them:


What the implications might be when it comes to their influence on radio propagation, if any, remains to be seen but I suspect that astrophysicists all over the world are having a close examination of long-held theories and the implications on their own fields of study.

You can read more details about this exciting discovery here.

(...cont'd)

* TWO: We need more technical showings this time, with as many solid
details as possible. I hope the Part 5 licensees are prepared to crunch
numbers, but those of us who only monitored are also able to contribute.
(Much more on this in future correspondence, I expect.) In par. 169. the FCC enquires: "to meet our goal of providing for the coexistence of amateur services and PLC systems in these bands, we seek detailed comment on the technical characteristics of both the PLC systems and the amateur stations.
This information will allow us to set an appropriate separation distance."
The very next sentence, though, I recognize as a somewhat worrisome bit of FCC-speak: "Although the Commission in the WRC-07 NPRM inquired into the technical rules and methods that would assure coexistence, commenters provided little in the way of concrete information." Read that as said with a slightly scolding tone, but with a facial expression that says they're keeping an open mind.

The utilities, IMO, provided no concrete technical information at all. ARRL
cited the 1985 NTIA study on which the 1 W EIRP and 1 km separation idea is based, but the FCC is concerned whether that's still valid. Well, one would hope that any changes made to PLCs over the past 30 years would be toward making the system more robust, not more vulnerable to evildoers, accidents, and natural disasters, but this could prove an area of contention. That may be something the big guys have to fight out; I don't know how much we as individual licensees or observers can contribute. But there ARE other technical matters the FCC needs and wants to know, which we may be able to furnish.

For instance, what sort of PLC signal levels have we actually experienced in the proposed bands? How serious were their impact on licensed activity, and how have PLCs been coped with in actual operation? Also at paragraphs 171, 178, and 178, the FCC is asking for some really fundamental, crucial data.
Namely: What sort of power levels have the Part 5 licensees actually
radiated, and at what actual separations from transmission lines? What
maximum size should an amateur antenna be, and--the biggie, in my view--what is the efficiency of both "typical" and potential amateur antenna systems?
(The Commission would like us to include information from Canadian and
European hams on these issues as well. Details of amateur practice in the
rest of the world could be very helpful in formulating rules here.)

Those operators who have the capability of measuring their true field
strength are in an especially excellent position to help quantify current
practice. Those who can't do that, but are able to measure their ground
losses accurately, can make reasonable calculations to show the maximum
efficiency possible with antennas of various heights. That's likely
preferable to doing it all in NEC modeling, since not all such software is
really good at predicting ground system losses, especially at LF. I'll
gladly offer my own ground system's resistance numbers to anyone who wants to do the math, for instance, as its 32 radials of 104 to 135 ft length in 15 mS/m soil are probably representative of a fairly decent ground for
antennas up to 100 feet high...and I'll be doing another set of readings
very soon, which can include measurements at 2200 m this year in addition to the runs I routinely do at 1750 m.

* THREE: At 172, the FCC observes: "If we were to adopt our proposal to
permit amateur operations only when separated by a specified distance from transmission lines, when a new transmission line is built close by an
amateur station, the station either would have to relocate farther away from the transmission line or cease operating." Scary, huh. But they go on to ask: "How should our rules address the potential for new transmission lines to be constructed closer than the specified distance to pre-existing amateur stations? We do not want to inhibit the ability of either PLC systems or amateur services to grow and expand without imposing unnecessary burdens on either. Is it possible for utilities to refrain from geographically expanding their PLC operations within the relatively small portion of the 9-490 kHz band that we are making available for amateur operations, and is this something utilities would do on their own accord, given the Part 15 status of PLC systems? Should our rules explicitly prohibit utilities from deploying new PLC systems in these bands?"

My answer: yes, please. Look back at par. 26, in the WRC-07 R&O section
where the Commission explains their basis for adding the 2200 m allocation:
"We intend to structure these service rules to promote shared use of the
band among amateurs and PLC systems. Amateurs will not be able to use their allocation status to force unlicensed PLC operations out of the band, and utilities will have no cause to abandon or incur large costs to modify
existing PLC systems." Read that again: "Amateurs will not be able to use
their allocation status to force unlicensed PLC operations out of the band."
That's the reality of the matter, and yet I think it also works in our
favor.

So far as I know, this situation is unique in the history of radio regulation. I can't think of another example where an incumbent, but unlicensed and unallocated, user of radio spectrum has been afforded such protection from any allocated and licensed service. However, most of us who commented in the 2013 proceeding DID AGREE with the Commission that PLC technology has been a special case for a long time, and most recognized that acceptance of its existence was the only way to move the discussion off dead center and get to the point where we are now.

But I maintain this coin has two sides. If we in a licensed, allocated service are willing to accept that we cannot displace existing PLCs now or in the future, then it is ONLY FAIR that the unlicensed, unallocated users should not be able to displace the licensed users, either, now or in the future. Otherwise, it is not truly sharing.

The only way I can see to guarantee protection to licensed users, comparable to what the unlicensed ones will have, is to incorporate within Part 15 a prohibition on any changes in power, transmission mode, and route of existing PLC systems, or installation of new ones, within a reasonable band centered on the new amateur allocations. That achieves the stated goal of not displacing existing systems or burdening the utlities by forcing any changes to them, while only removing two small slices of spectrum from consideration for future installations. That seems an entirely reasonable compromise to me.

Your comments are welcome--and essential!

73
John Davis


You can view comments as well as file your own, via the link from this page:

http://apps.fcc.gov/ecfs/proceeding/view?name=15-99