(From The LOWDOWN, September, 1997) "The LF Notebook" The Mailbag, News and Comments About LF Radio, Etc. John H. Davis, Box 367, Warm Springs, GA 31830 - E-mail - longwave@mindspring.com - Web - http://members.aol.com/lwcanews/ [ ONE PICTURE ACCOMPANIES THIS ARTICLE: ] http://frodo.bruderhof.com/longwave/notebook/n54pic1.jpg Testing...1...2...3... Well. It's nice to be back on the air; or, "on the paper," more accurately. The last page of last month's column was literally the last page my faithful old Epson may ever put out. When I returned from the Post Office after mailing the column, it wouldn't even try to print again. After four years' excellent service (and, alas, a new and now-useless toner cartridge) the fuser assembly said "that's all, folks." A replacement costs slightly more than a new NEC SuperScript 860, even counting the extra RAM it takes to print graphics on legal-size paper. Go figure. At any rate, the NEC seems to do quite nicely, although there will probably be a noticeable difference in print appearance. Its higher native resolution will mean more delicate lines and curves in some of the lettering, which may be a little harder to see in the journal. Or who knows...it might show up better. Time will tell. One really nice feature is the ability to render halftone images in a variety of resolutions and dot patterns. Maybe our printing crew won't have to consume too much Maalox trying to reproduce such pictures. The old laser printer offered only one resolution, and I'm sure it was awkward to reduce pages to the final size while retaining any semblance of dot structure on the printing plate. It'll probably be another month or two before we can tell about this, though; the only photo in this month's Notebook is one I scaled up in size, so it's going to look a little ragged anyway. I can already tell I'll have to postpone at least some of the material I'd like to use this time. I'm installing the printer on the night when I should be printing the final result, and have yet to lay out the contents of the column. Apart from the budget setback, a little too much Georgia heat during a lightning protection project has put me literally under the weather, and resulted in a big slowdown too. (I'm thinking of selling my story as a soap opera: The Edge of Geezerhood.) Fortunately, we do have other articles available this month, so I hope you'll forgive the brevity this time. Look for an improved column in October. Another LF Ham Band Progress marches on toward a global Amateur Radio presence on longwave. Jacques d'Avignon (Radio Propagation Forecasting & HF Monitoring Services, Kingston, ON; monitor@rac.ca) reports that "Since April 1st, the Finnish hams can now used the following frequency band for their operation: 135.7 to 137.8 kHz. Authorized output power is 100W. I do not know what mode(s) is/are permitted." We'll try to find more on this in coming weeks. Followup: WWVB As mentioned last time, I placed an inquiry about the anticipated antenna radiation pattern for the improved WWVB transmitting installation. Matthew Deutch, with NIST in Boulder, graciously responded with the following information: "I enjoyed reading your article in this month's Lowdown. I regret that I must inform you that our new projected high power testing date is December, 1997. It was becoming apparent that September was just not realistic." "When we incorporate the WWVL antenna into the WWVB system it will create a slight directional pattern. Some computer modeling shows that the east to west pattern will be about 1db stronger than the north to south. We are also hoping to post, at our web site, some of the projected signal contours. These too will be computer generated." "We may also be able to provide you with some information on the FRT-72. The 72's are new to us so we are still learning." Followup: Atmospheric Stuff Two publications featured articles on lightning research this summer. David Jones (NR, Columbus GA; d.jones160@genie.com) advises that the August issue of Scientific American has two articles on lightning. "One is about instigating lightning with lasers. The second is about sprites and blue-jets. Stanford U. has been recording the radio frequency from Walt Lyons lookout over the great plains this summer." New member Stephen Gutierrez found another interesting article, too: "In the August/September issue of Weatherwise there is a good article on these strange forms of lightning. Lots of pictures, diagrams and information on observing red sprites yourself. The article is written by Walter A. Lyons." Dr. Lyons' Web site was listed at the end of the article as: www.FMA-research.com Fun With NDBs Online One of the most common requests to the Longwave Home Page has been for a source of international NDB information online. While U.S. aero beacons can be searched at the AirNav site, and Pierre Thompson maintains an online site of Canadian beacons, it has been difficult to find an electronic source for others around the world. Patty Winter (N6BIS; patty1@home.com) found one, in Ireland. It's: http://homepages.iol.ie/~markzee/wand.htm It contains more than 9,000 VORs and NDBs, and is listed in both Excel and plain text formats. Both are zipped files. The Canadian list is at http://frodo.bruderhof.com/ka2qpg/ while the U.S. areo beacons can be found at: http://www.airnav.com/ On to the Mailbag... -Lyle Koehler (LEK, MIN, K0LR; Aitkin, MN; k0lr@emily.net) passes along some remarkable news this month: "LowFER beacon OK is readable here in Minnesota this morning (Aug. 14) at 0845 local time. First LowFER DX in a several months. SAM is also coming in better than it has all summer; there's hope that the QRN season will eventually come to an end." -Bob A. Hoffswell (BOB; AA9DH; Mahomet, IL; harvey@prairienet.org) reports, "BOB is still on 24 hrs with a ground-screen only. It works, but not very well, and acts as a leaky capacitor when the ground and it are wet, which affects antenna loading. Conditions have been pretty summer-like, with lots of QRN. I've not heard BA for sometime, but hope to catch him again in August, as I did last year. I'm planning to go visit Brice later this summer, when we set up a date for a tour of his stuff and the bright spots of Lancaster." "I've done some initial work looking at grounds and have set up several rods here and there, all about 9' long, copper pipe. I did it to see how one-line telegraph worked, and it works fine! Although the apparant resistance varies with ground conditions, it's about 20 ohm or so for the rods and not a function of the distance between them--unlike a resistor. It's the earth condition in the immediate vicinity of the rod that counts, and not the path between rods (5 ft or 500 ft makes little difference)." "I tried a Bunnell relay and a 6v. battery for the test, and later a resistor and the battery to give a 100mA source for the test. Because of some polarizing effects with DC, an AC test would propably be better, and I hope to do that sometime soon." "I found a copy of Terman's Radio Engineering Handbook (1942), and he has a lot to say about LF, including info that indicates the depth of field penetration into the earth as a function of frequency. i.e. at 180kHz, the field at 50 ft down is about 75% of its value at the surface! It seems one could bury most of a LowFER antenna and still have a great antenna! (The FCC doesn't say how far down we can go!)" -Dick Wilder (K3DI; wilder@clark.net; Arnold, MD 21012-1724) announces, "In a few weeks, I should be on LF. I have a transmitter going (subject to more revisions) and really just have to put in a grid-block keying circuit and put up an antenna. The rig is VFO controlled so my first task will be to find a frequency. I'll start on 180.000 kHz but let you know my final frequency. Initially, I will come on when scheduled either day or evenings (I'm retired) but subsequently I expect to get into 24-hour beacon mode." -Darwin Long (DJL; DJL4LOONS@aol.com) wants to "give everyone a quick update on the status of a DGPS beacon I discussed a few months back from Pt. Atkinson, BC. I was up in the Pacific Northwest and Canada again this past month. The DGPS beacon at Point Atkinson is still transmitting its +400Hz ID AE on top of the main 320 kHz MSK carrier. I made another set of recordings if anyone is interested. Are there any other LWCA members out there in the Northwest area hearing this DGPS beacon? This beacon has been operating this way now for almost three years." "I was able to pick up the Appleton, WA, DGPS signal (from the converted GWEN site), in Whitefish and Seeley Lake, MT, and also in Kamloops, BC, via groundwave during the day." "There seems to be an increase in 'private' NDB's in southwest Canada this year. (NDBs with an alphanumeric two-digit ID.) Most of these are little 25 W NDBs with double sideband transmission of 400Hz shift. The umbrella-type antenna stands about 25 feet high and is center-loaded. The transmitter is in a small metal box, usually affixed to the base of the antenna mast. I guess these are 'economy' NDBs, quick and easy to install and switch on." Darwin's photo of 6K (302 kHz, DSB 400Hz), Vernon, BC, is N54PIC1.JPG. While somewhat more rudimentary in appearance than "big time" NDBs, its design certainly looks familiar to LowFERs, and ought to give quite respectable results. Darwin confirms that this is indeed the case. "I could copy them easily for a radius of 200 miles or more. (Beacon 6K) is a new private NDB belonging to a company called Swan Lake. I stumbled on it while trying to find NY 350kHz in Enderby, BC. By the way, has ANYONE ever successfully DF'ed NY 350? I just couldn't find it. It seems to be up in the mountains to the west of Enderby." "I now have my own internet account, instead of sharing one. Therefore, my e-mail address has changed yet again! (And will probably be the final change, too)." "DJL has been intermittent due to a blown final, and then a worn-out keyer relay, so I upgraded the 2A relay to a 10 A one, and went from a 2N3055 to a 2N3772 final. All is well at this point. Don't blow your ears with the lightning crashes, and have a good summer." -John Reed (jtreed@poncacity.net) sent the conclusion of his series on weak signal reception, which may appear elsewhere in this issue. He's also been listening. "I heard TEXAS for the first time in many weeks this afternoon (Aug. 3). On Sundays, the line noise is usually better. I hope this is an indication of good DXing in the future." "I'm using a new receiver here, a Harris RF-550. I like it because it's the only synthesized digital readout receiver I've seen that is perfectly quiet alongside a loop. It has a good S/N rating and 500 Hz filter. I plan to install another homebrew crystal filter of 100 or 200 Hz bandwidth later." -Cliff Buttschardt (HDO, K7RR; cbuttsch@slonet.org) advises, "Today, all of us on BPSK have been trying to interest G3IRM in the UK to get on. We all hear a few CQ's and nothing more. The first few attempts at BPSK are difficult, so this is a real accomplishment. " "BPSK in the summer is really a good replacement for LowFER listening. In fact, there have been a number of unscheduled contacts on 7081 anytime between 0130 and 0230 UTC. Except for the path between Bill Lake and myself, that frequency seems the most popular." Footnotes. In addition to the CONSOL material from Don Schimmel and Greg Hardison that I had to postpone again, I've also received Jon Iza's translation of an amateur radio article from Spain that adds to the subject. Look for these next time. There's also some activity right now in developing receivers and/or software for Differential GPS DXing. We hope to have a summary of that ready for you. Those looking for descriptions of good LowFER beacon antenna construction techniques won't be disappointed, either. A much- appreciated letter from Herb Vanderbeek reveals how his beacon G couples to the ether. Also, we've got a couple of lists of unusual Canadian NDBs that will challenge even the most jaded DXer, courtesy of Jacques d'Avignon. And there's likely to be plenty more. It should be an interesting issue. Let's have your news, too. 73. - - -