Re: Topband: Pulleys for antennas in trees
On Tue,1/27/2015 9:50 AM, Mel Crichton wrote: So if using a pulley, please be sure the supporting branch is stout I had to replace the windshield of my truck to prove this point to me. I find it best to install inverted vee type (center supported) dipoles or very light inverted L's to minimize the sideways stress on the branch (sideways stress intensifies when the wind blows hard). And yes I have pulleys high in trees. Hi Mel, I can't dispute your mechanical engineering and rigging thoughts, but I strongly prefer flat dipoles if I can rig them. So does N6BT, the excellent antenna engineer behind the original Force 12 antennas, who observes that the performance of the antenna will be dependent on its average height. Quite a few years ago, I saw a piece in QST stating that a lag screw going horizontally into the trunk of tree was one of the least invasive ways to rig an antenna. That means, of course, that someone has to climb the tree. My wire antennas are mostly rigged that way. Since the subject line is about pulleys, I'll link to the pulley I use. It's a really neat pulley, and is sold out here by stores who cater to arborists and tree climbers. http://www.cmi-gear.com/collections/frontpage-2-service-line-pulleys/products/rp115 Here's a photo of the pulley and the lag screw. k9yc.com/Pulley.JPG I use the 5/16-in rope distributed by Synthetic Textiles. DX Engineering and HRO also sell it. I use the 5/16-in size because it's big enough to be able to grab it hard enough to put a lot of tension on it. It's a double-braid polyester rope with a black outer sheath that provides UV protection. http://www.synthetictextilesinc.com/supportham.html My wires are up 130 ft in redwoods, so they need pretty robust rigging hardware. Not everyone needs stuff this robust. :) Another important rigging element for any wire in a tree is a weight below a pulley terminating one end of the antenna to provide some give for tree sway. There are many ways to skin this cat, including old window weights and cement in a bucket. I use big water jugs that I fill with dry sand. I'm typically using 70-90 pounds of tension. 73, Jim K9YC _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: K levels and skew path on 160
I was rereading the article by Cary Oler and Ted Cohen (N4XX), published in 1998, which provided a good primer for understanding, as much as we can, propagation on Topband. In one section the impact of a high K index on the auroral oval, and its subsequent impact on signals passing through the oval, was discussed. My question is does the K index, especially at higher levels, impact the SW or SSW skew path many of us were trying to use this morning to work Ken, XW4ZW? Any information or observations will be appreciated. Best, Steve, From my location now, and when I was in Ohio, it was quite normal for any signal passing near or through the north magnetic pole to never make it through via the direct path. When signals were heard, they were always skewed in some other direction. The only exception seems to be when sunspots and geomagnetic activity are very low. In this very last solar minimum, when sunspots were absent, many stations would appear via north. Of course that gave the northern NA stations nearly north of me a clear advantage, because they were closer. My policy is to not worry about predicting or expecting anything, and I rarely even look at solar activity. I just listen in all dark directions when the station is almost on the opposite side of the world, especially when he is anywhere near the equator and far,far, away. :) 73 Tom _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Elimination of Treadmill RFI on 160 meters
Hi Brad, Great to hear you had similar results. The 20VR1 and the 20DRGG5 filter appear to be of very similar design (two stage filters, and component values not vastly different). The 20VR1 looks to be double the price of the 20DRGG5, but it might offset some of the additional cost if it allows elimination of the additional Toroid core choke. Since all cases are different I would have to test the 20VR1 in my application to see if it would indeed allow elimination of the Toroid core choke, but I doubt I would be able to eliminate the Toroid core choke for the following reason that Jim K9YC mentioned on another reflector : What the power industry calls common mode is NOT what we call common mode. They are talking about the voltage between neutral and the green wire. We are talking about current that is flowing in the same direction on three conductors. In my case the additional Toroid core choke had a very noticeable impact, and I now can't tell when the treadmill is on when using the combination of both filters. P.S. I sent an e-mail to the manufacturer of our Treadmill, and they never responded. I am now going to call them on the phone in an attempt to get in touch with their design engineers, and likely will also file a complaint with the FCC regarding treadmills in general. There are a couple more treadmills near my home that generate very strong RFI, but fortunately they normally use their Treadmills during the day, and I operate mostly at night. 73, Don (wd8dsb) On Tue, Jan 27, 2015 at 1:26 PM, Brad Rehm bradr...@gmail.com wrote: Don, FWIW, today, W5UJE and I dealt with a treadmill problem similar to yours by installing a commercial line filter between the line and the treadmill electronics. A Corcom/TE Connectivity 20VR1 filter reduced the 40m and 75m noise at his receiver from S9+10db to less than S2 (his noise floor this morning). The 20 Amp rating was needed because the manufacturer's published current requirement for the treadmill was 15 Amps. In measurements we'd made earlier, we found that this was a common-mode problem and that the noise spurs were about 20 kHz apart when the treadmill was operating under a moderate load. The spectrum scope on his radio showed 20 kHz-spaced broadband noise up through 29 MHz, peaking between 1.8 and 15 MHz. The line filter we chose offers 10-20 dB of supperssion below 50 kHz and 60-80 dB of suppression between 300 kHz and 29 MHz. No additional filtering with torroids or capacitors was needed. In other words, our results were similar to yours, and one wonders how manufacturers can say these things meet Part 15 requirements for conducted emissions. Brad KV5V On Mon, Jan 26, 2015 at 7:22 PM, Don Kirk wd8...@gmail.com wrote: Treadmill combination filter update. Today I replaced the 10 amp commercial filter with the 20 amp version of the filter, and the results are similar. Below are a few measurements on 160 meters and 80 meters showing how effective the combination of the two filters are (14 turn toroid choke, and commercial filter model 20DRGG5 made by Delta) in reducing my treadmill RFI. *1.8068 Mhz* No Filters : 19db over S9 With Filters : S7 which is my noise floor *1.8291 Mhz* No Filters : 15db over S9 With Filters : S7 which is my noise floor *3.5250 Mhz* No Filters : 28db over S9 With Filters : S6 which is my noise floor *3.5475 Mhz* No Filters : 25db over S9 With Filters : S6 which is my noise floor The 3.5250 Mhz readings indicate the filter is knocking the signal down at least 46db (and probably more). 73, Don (wd8dsb) _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: K levels and skew path on 160
From mid-November through mid-February, daylight over Antarctica and the Southern Ocean prevents the 160 meter long path from propagating due south (+/- about 20 degrees). Except for sunspot minimum, short path propagation transiting only the northern hemisphere to southeast Asia is very uncommon from the eastern USA. 160 and 80 meter propagation from eastern USA to southeast Asia is most likely to follow the SSE evening and SSW sunrise gray lines, although as Tom says, its best to listen for the actual path. From 1145-1300Z (the likely times for long path propagation to southeast Asia during eastern USA morning) the gray line passes approximately through HC8, so the long path is likely to be SSW or possibly SW Because the southern magnetic pole is just off the coast of Antarctica and directly south of Australia, the SSW long path crosses through the auroral belt and this long path is significantly affected by geomagnetic activity. From 2300-2330Z (the most likely times for southeast Asia long path in eastern USA evening) the grey line crosses Uruguay, so the long path to southeast Asia is likely to be SSE or possibly SE. Because the southern magnetic pole is on the opposite side of Antarctica, the SSE long path is much less affected by geomagnetic conditions than the 1145-1300Z SSW long path. 73 Frank W3LPL - Original Message - From: Tom W8JI w...@w8ji.com To: Steven R Daniel, D.D.S. n...@comcast.net, topband@contesting.com Sent: Tuesday, January 27, 2015 7:21:00 PM Subject: Re: Topband: K levels and skew path on 160 I was rereading the article by Cary Oler and Ted Cohen (N4XX), published in 1998, which provided a good primer for understanding, as much as we can, propagation on Topband. In one section the impact of a high K index on the auroral oval, and its subsequent impact on signals passing through the oval, was discussed. My question is does the K index, especially at higher levels, impact the SW or SSW skew path many of us were trying to use this morning to work Ken, XW4ZW? Any information or observations will be appreciated. Best, Steve, From my location now, and when I was in Ohio, it was quite normal for any signal passing near or through the north magnetic pole to never make it through via the direct path. When signals were heard, they were always skewed in some other direction. The only exception seems to be when sunspots and geomagnetic activity are very low. In this very last solar minimum, when sunspots were absent, many stations would appear via north. Of course that gave the northern NA stations nearly north of me a clear advantage, because they were closer. My policy is to not worry about predicting or expecting anything, and I rarely even look at solar activity. I just listen in all dark directions when the station is almost on the opposite side of the world, especially when he is anywhere near the equator and far,far, away. :) 73 Tom _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Elimination of Treadmill RFI on 160 meters
Don, You make a good point about the difference between our definition of CM noise and the definition implied in Part 15. If the external torroid made a difference for you, then it's important and worth having. We can't be too optimistic about the manufacturer's interest in fixing this kind of problem. He won't be willing to install a $50 or even $25 filter to satisfy a few hams who have EMC complaints. At the same time, because the products you and I have dealt with responded so well when we added filters, we have to wonder if and how the Part 15 compliance testing was done. In the EMC lab where I worked, we tested them under load (with someone walking on the treadmill or with a fixed load applied), but some labs might be tempted to test only the uP controller. It's hard to imagine how this could be justified, because the belt is usually driven with square pulses. RF noise from these can be hard to suppress. I didn't think to check the label for the machine I worked on, but I wonder if you've looked for an FCC compliance mark on your treadmill. If it has one, it might be interesting to go to the FCC URL and look at the report that was filed for it. And BTW, if the treadmill was manufactured in the far east, the mark could be bogus or filtering could have been deleted after the initial testing was done. This kind of thing isn't all that unusual. 73, Brad KV5V On Tue, Jan 27, 2015 at 4:05 PM, Don Kirk wd8...@gmail.com wrote: Hi Brad, Great to hear you had similar results. The 20VR1 and the 20DRGG5 filter appear to be of very similar design (two stage filters, and component values not vastly different). The 20VR1 looks to be double the price of the 20DRGG5, but it might offset some of the additional cost if it allows elimination of the additional Toroid core choke. Since all cases are different I would have to test the 20VR1 in my application to see if it would indeed allow elimination of the Toroid core choke, but I doubt I would be able to eliminate the Toroid core choke for the following reason that Jim K9YC mentioned on another reflector : What the power industry calls common mode is NOT what we call common mode. They are talking about the voltage between neutral and the green wire. We are talking about current that is flowing in the same direction on three conductors. In my case the additional Toroid core choke had a very noticeable impact, and I now can't tell when the treadmill is on when using the combination of both filters. P.S. I sent an e-mail to the manufacturer of our Treadmill, and they never responded. I am now going to call them on the phone in an attempt to get in touch with their design engineers, and likely will also file a complaint with the FCC regarding treadmills in general. There are a couple more treadmills near my home that generate very strong RFI, but fortunately they normally use their Treadmills during the day, and I operate mostly at night. 73, Don (wd8dsb) On Tue, Jan 27, 2015 at 1:26 PM, Brad Rehm bradr...@gmail.com wrote: Don, FWIW, today, W5UJE and I dealt with a treadmill problem similar to yours by installing a commercial line filter between the line and the treadmill electronics. A Corcom/TE Connectivity 20VR1 filter reduced the 40m and 75m noise at his receiver from S9+10db to less than S2 (his noise floor this morning). The 20 Amp rating was needed because the manufacturer's published current requirement for the treadmill was 15 Amps. In measurements we'd made earlier, we found that this was a common-mode problem and that the noise spurs were about 20 kHz apart when the treadmill was operating under a moderate load. The spectrum scope on his radio showed 20 kHz-spaced broadband noise up through 29 MHz, peaking between 1.8 and 15 MHz. The line filter we chose offers 10-20 dB of supperssion below 50 kHz and 60-80 dB of suppression between 300 kHz and 29 MHz. No additional filtering with torroids or capacitors was needed. In other words, our results were similar to yours, and one wonders how manufacturers can say these things meet Part 15 requirements for conducted emissions. Brad KV5V On Mon, Jan 26, 2015 at 7:22 PM, Don Kirk wd8...@gmail.com wrote: Treadmill combination filter update. Today I replaced the 10 amp commercial filter with the 20 amp version of the filter, and the results are similar. Below are a few measurements on 160 meters and 80 meters showing how effective the combination of the two filters are (14 turn toroid choke, and commercial filter model 20DRGG5 made by Delta) in reducing my treadmill RFI. *1.8068 Mhz* No Filters : 19db over S9 With Filters : S7 which is my noise floor *1.8291 Mhz* No Filters : 15db over S9 With Filters : S7 which is my noise floor *3.5250 Mhz* No Filters : 28db over S9 With Filters : S6 which is my noise floor *3.5475 Mhz* No Filters : 25db over S9 With Filters : S6 which is my noise floor The 3.5250 Mhz readings
Re: Topband: Elimination of Treadmill RFI on 160 meters
are talking about current that is flowing in the same direction on three conductors. In my case the additional Toroid core choke had a very noticeable impact, and I now can't tell when the treadmill is on when using the combination of both filters. P.S. I sent an e-mail to the manufacturer of our Treadmill, and they never responded. I am now going to call them on the phone in an attempt to get in touch with their design engineers, and likely will also file a complaint with the FCC regarding treadmills in general. There are a couple more treadmills near my home that generate very strong RFI, but fortunately they normally use their Treadmills during the day, and I operate mostly at night. The FCC requires testing of power line conducted emissions with a line sample unit that connects from each conductor to ground. One LISN is specified to go from each current-carrying conductor to ground. The safety ground, since it does not carry current, is grounded. The flaw in this system is that differential voltages between current carrying wires are not measured, and anything on the safety ground isn't measured. Noise voltage is only measured from individual current carrying conductors to ground, and the safety ground is grounded and not measured. Filters inside devices and many outside filters often route the noise right out on the safety ground, in differential to the equipment case (if large it acts like a groundplane) or other connecting wired systems like a Telco line or data interface cable. Since the FCC mandates the safety ground and other grounds be grounded to the test equipment RF measurement groundplane, that path or ground loop paths are not measured. This allows some pretty ratty stuff to pass FCC tests. The FCC should have created a better test, instead of assuming all grounds in the real world were common-connected with near zero impedance. 73 Tom _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: K levels and skew path on 160
I was rereading the article by Cary Oler and Ted Cohen (N4XX), published in 1998, which provided a good primer for understanding, as much as we can, propagation on Topband. In one section the impact of a high K index on the auroral oval, and its subsequent impact on signals passing through the oval, was discussed. My question is does the K index, especially at higher levels, impact the SW or SSW skew path many of us were trying to use this morning to work Ken, XW4ZW? Any information or observations will be appreciated. Best, Steve, NN4T _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Elimination of Treadmill RFI on 160 meters
On Tue,1/27/2015 3:19 PM, Brad Rehm wrote: You make a good point about the difference between our definition of CM noise and the definition implied in Part 15. If the external torroid made a difference for you, then it's important and worth having. Exactly. The commercial filter addresses only differential mode. The ferrite choke is necessary to suppress what we (and Part 15) call common mode. Several years ago, I put some good quality line filters in electrical boxes for use on Field Day and California QSO Party county expeditions with our Yamaha generators. They didn't do much -- to kill the moderate trash, I had to to wind multiple turns of the line cord through a big ferrite core. I used a big 1-in i.d. Fair-Rite #31 clamp-on that's a couple of inches long (the biggest they make). Depending on the diameter of the line cord I had used, I was able to get either three or four turns through it. That was enough to kill 20-10M, which is what we heard in the tri-banders that were close to the generator, and for the 80/40 dipoles that were much further away. If the 80/40 antennas had been closer we would likely have needed more turns. Did the commercial line filters do any good? I don't know -- but they certainly didn't hurt, and the boxes I put them in have a bunch of outlets on them for power distro. :) OTOH, one of the guys used to bring his big RV with a noisy generator on-board. All I used there was as many turns as I could get through a small stack of 1.4-in i.d. #31 toroids as close as I could get them to the generator, and it did the job. 73, Jim K9YC _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: K levels and skew path on 160
-Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of donov...@starpower.net Sent: Tuesday, January 27, 2015 3:28 PM To: topband@contesting.com Cc: n...@comcast.net Because the southern magnetic pole is just off the coast of Antarctica and directly south of Australia, the SSW long path crosses through the auroral belt and this long path is significantly affected by geomagnetic activity. From 2300-2330Z (the most likely times for southeast Asia long path in eastern USA evening) the grey line crosses Uruguay, so the long path to southeast Asia is likely to be SSE or possibly SE. Because the southern magnetic pole is on the opposite side of Antarctica, the SSE long path is much less affected by geomagnetic conditions than the 1145-1300Z SSW long path. Frank Your observations match my observations since 2009 when I started to work with Horizontal polarized receiver antenna for 80/160. 2010 and 2011 the SSE/SSW path was open most of the days. Peter (XU7ACY) was very active and I heard him from October to March over 60 days out of 180 days on 160m, and every single day on 80m at the same operating time you mentioned. I did try to correlate the openings with K and AL and it is not directly related. The only index for magnetic storm that was correlated was Dst. Dst index is an index of magnetic activity derived from a network of near-equatorial geomagnetic observatories that measures the intensity of the globally symmetrical equatorial electrojet (the ring current). I started to follow Dst because Alan Melia G3NYK long wave propagation page. Alan noticed the LF ( 500KHz) propagation could be good after few days of Dst above zero, it means low activity of magnetic storm. K, AL and Dst and all related with solar wind speed, predictions are available from Colorado and Kyoto. http://lasp.colorado.edu/space_weather/dsttemerin/dsttemerin.html http://wdc.kugi.kyoto-u.ac.jp/dst_realtime/presentmonth/index.html The Dst can be useful when is positive for 5 or more days, indicating good condition possibility. Activity is more important than possibility, without activity propagation does not matter. So when a flare or CME hit the magnetic ring, two things happen, first there is a very good improvement on the propagation for few hours followed by a depression and degradation of propagation, that depression last for several days and a good recovery can take over a week. After the impact the attenuation is high above normal and the impact on 160m is significate, but not much on 80m. After a good success with HWF in Florida, some friends in South America, and Brazil started to use the HWF for long path. I get very serious trying to understand the physics behind 50% openings on LP and I collect data from previous QSO on 80 and 160m when directive RX antenna systems was used. For my surprise all opening on the South Hemisphere long path were actually NNW NNE. That result indicate that the actual signal SSE SSW get refracted at the equator region and travel inside the darkness. Robert DU7ET was a good example of this kind of propagation long path , we had QSO's every month from Jan to July 2013. For me all openings were SSW but from my friends on Brazil the path was NNW. Based on the observations my conclusion (still a work in progress) is that the signal does not reach the south pole auroral belt. It's run along the equator, That s why I am calling this propagation mode TELP , Trans Equatorial Long Path. Carl K9LA did a nice paper with the ray traces from my location to XU7 , and at 40 degree there is a refraction bending SSW signal to W. It can explain the same bending for reflated signals NNW to W from Brazil. Dst also can show how bad the propagation was Dec 2014 to middle Jan 2015. Ove several years the Dst was in between 0 and -20 but during the last two month Dst was between -20 and -40 with very deeps near -100. I would say that TELP I open on 80m almost every day, we just don't have much activity to understand it better. Regards JC N4IS - Original Message - From: Tom W8JI w...@w8ji.com To: Steven R Daniel, D.D.S. n...@comcast.net, topband@contesting.com Sent: Tuesday, January 27, 2015 7:21:00 PM Subject: Re: Topband: K levels and skew path on 160 I was rereading the article by Cary Oler and Ted Cohen (N4XX), published in 1998, which provided a good primer for understanding, as much as we can, propagation on Topband. In one section the impact of a high K index on the auroral oval, and its subsequent impact on signals passing through the oval, was discussed. My question is does the K index, especially at higher levels, impact the SW or SSW skew path many of us were trying to use this morning to work Ken, XW4ZW? Any information or observations will be appreciated. Best, Steve, From my location now, and when I was in Ohio, it was quite normal for any signal passing near or through the north magnetic pole to never make it
Re: Topband: Elimination of Treadmill RFI on 160 meters
On Tue,1/27/2015 4:08 PM, Tom W8JI wrote: The flaw in this system is that differential voltages between current carrying wires are not measured, and anything on the safety ground isn't measured. Noise voltage is only measured from individual current carrying conductors to ground, and the safety ground is grounded and not measured. Exactly right, Tom. A common design/manufacturing defect is that the green wire fails to make contact with the shielding enclosure, but instead goes to common on a circuit board, which may or may not ever find the chassis. This defect, which is the power system equivalent of a Pin One Problem, puts noise on the green wire. You may remember that we corresponded several years ago about Astron power supplies, in which a very common defect is that the green wire is soldered to the mounting lug of a terminal strip, which is insulated from the chassis by paint. The same mounting lug is the point where V- is bonded, so it never finds the chassis either. AND, wiring for both V- and the green wire act as antennas for both TX and RX. I have long suspected that similar defects are at least partially responsible for noise conducted onto coax and AC lines from consumer products of all sorts. 73, Jim K9YC _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: K levels and skew path on 160
Hi JC, Thanks for your interesting email. You may be correct that SSE/SSW long path propagation may not extend very far into the southern hemisphere. I wasn't aware of the NNE/NNW observations by our southern hemisphere friends. It also appears that SSE/SSW long path is more reliable for more southerly locations in the USA than it is for higher latitude locations. Unfortunately there usually isn't enough activity in southeast asia for us to make regular observations, you were fortunate to be able to have long term observations with XU7ACY and DU7ET . Thanks 73 Frank W3LPL - Original Message - From: JC n...@comcast.net To: donov...@starpower.net, topband@contesting.com Cc: n...@comcast.net Sent: Wednesday, January 28, 2015 2:45:05 AM Subject: RE: Topband: K levels and skew path on 160 -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of donov...@starpower.net Sent: Tuesday, January 27, 2015 3:28 PM To: topband@contesting.com Cc: n...@comcast.net Because the southern magnetic pole is just off the coast of Antarctica and directly south of Australia, the SSW long path crosses through the auroral belt and this long path is significantly affected by geomagnetic activity. From 2300-2330Z (the most likely times for southeast Asia long path in eastern USA evening) the grey line crosses Uruguay, so the long path to southeast Asia is likely to be SSE or possibly SE. Because the southern magnetic pole is on the opposite side of Antarctica, the SSE long path is much less affected by geomagnetic conditions than the 1145-1300Z SSW long path. Frank Your observations match my observations since 2009 when I started to work with Horizontal polarized receiver antenna for 80/160. 2010 and 2011 the SSE/SSW path was open most of the days. Peter (XU7ACY) was very active and I heard him from October to March over 60 days out of 180 days on 160m, and every single day on 80m at the same operating time you mentioned. I did try to correlate the openings with K and AL and it is not directly related. The only index for magnetic storm that was correlated was Dst. Dst index is an index of magnetic activity derived from a network of near-equatorial geomagnetic observatories that measures the intensity of the globally symmetrical equatorial electrojet (the ring current). I started to follow Dst because Alan Melia G3NYK long wave propagation page. Alan noticed the LF ( 500KHz) propagation could be good after few days of Dst above zero, it means low activity of magnetic storm. K, AL and Dst and all related with solar wind speed, predictions are available from Colorado and Kyoto. http://lasp.colorado.edu/space_weather/dsttemerin/dsttemerin.html http://wdc.kugi.kyoto-u.ac.jp/dst_realtime/presentmonth/index.html The Dst can be useful when is positive for 5 or more days, indicating good condition possibility. Activity is more important than possibility, without activity propagation does not matter. So when a flare or CME hit the magnetic ring, two things happen, first there is a very good improvement on the propagation for few hours followed by a depression and degradation of propagation, that depression last for several days and a good recovery can take over a week. After the impact the attenuation is high above normal and the impact on 160m is significate, but not much on 80m. After a good success with HWF in Florida, some friends in South America, and Brazil started to use the HWF for long path. I get very serious trying to understand the physics behind 50% openings on LP and I collect data from previous QSO on 80 and 160m when directive RX antenna systems was used. For my surprise all opening on the South Hemisphere long path were actually NNW NNE. That result indicate that the actual signal SSE SSW get refracted at the equator region and travel inside the darkness. Robert DU7ET was a good example of this kind of propagation long path , we had QSO's every month from Jan to July 2013. For me all openings were SSW but from my friends on Brazil the path was NNW. Based on the observations my conclusion (still a work in progress) is that the signal does not reach the south pole auroral belt. It's run along the equator, That s why I am calling this propagation mode TELP , Trans Equatorial Long Path. Carl K9LA did a nice paper with the ray traces from my location to XU7 , and at 40 degree there is a refraction bending SSW signal to W. It can explain the same bending for reflated signals NNW to W from Brazil. Dst also can show how bad the propagation was Dec 2014 to middle Jan 2015. Ove several years the Dst was in between 0 and -20 but during the last two month Dst was between -20 and -40 with very deeps near -100. I would say that TELP I open on 80m almost every day, we just don't have much activity to understand it better. Regards JC N4IS - Original Message - From: Tom
