notebk32.txt The LF Notebook: The Mailbag, News and Comments About LF Radio, Etc. John H. Davis, Box 367, Warm Springs, GA 31830 -E-mail: johnhdavis@aol.com -Fax/Answering Machine: (706) 672-0964 -Longwave/Part 15 BBS: 706/672-0360 (from the November, 1995, issue of The LOWDOWN) Ecstatic Indians or bombastic Braves? We'll know the outcome of the World Series by the time you read this, I suppose. (*We do. The Braves won!) Kind of a small column this month, but it may be just as well under the circumstances. As I mentioned in the 1750 Meter column, we had a little hurricane here. Power was off four days, so there was no BBS, fax, answering machine, or even electric typewriter for writing or otherwise communicating with anyone. That was followed by a few more days of cleanup...then a week and a half of flu. Unfortunately, while the power was out, there was no time to conduct any whistler listening. But during the days of lung congestion, my breathing contained an abundant variety of clicks, tweaks, whistles, dawn chorus and auroral emissions! Well, I'm back to my usual semi-normal state now, and can't really complain. In fact, if you've got to have a hurricane, you couldn't ask for better weather than we had for the cleanup operation. The skies were the most gorgeous clear blue, and we didn't need air conditioning in the day or heat at night. The usual end-of-September 15 degree temperature drop held off until the 14th of October, at which time the sky abruptly changed to its autumn mix of high clouds, the light became yellower in the afternoon, and that highlighted the sudden change in color of some of our foliage. All at once, right on cue, as it were. New beacons pending. You may notice in the listings (and in the Mailbag) that two new LowFERs are in the works from North Carolina. One of our more populous but under-represented states, Florida, may be seeing more beacon activity too. Norm Wilford, W1TLZ (3630 Hightower Court, Cocoa, FL 32926-4484) is plan- ning to get back on the air around 189 kHz, though he did not specify a call sign. And, he says, "possibly on the 'hi-band' this winter." Don Burns, K4GHD, Plantation, Florida (near Ft. Lauderdale) is getting ready to fire up his first LF beacon. No frequency has been mentioned yet. He would appreciate suggestions on the most effective format for making his ID copiable. (E-mail addresses: epur01@email.mot.com or donburns@shadow.net.) The Periodical Shelf - Richard V. Hague, Las Vegas, NV, mentions an ELF-related article, "Mystery in Alaska," on page 79 of the September Popular Science. - Do not, under any circumstances, miss the Field Day results on page 119 of the November QST! There you will see a genuine, (probably) unretouched photo of Tod Olson (K0TO and former LowFER TO), and our own Lyle Koehler (K0LR, LEK, and MIN) demonstrating how the Minnesota Wireless Association manages to put out signals on Field Day. - Still more on the powerline fields controversy...the journal New Scientist this month published what it called a leaked report from the U.S. National Council on Radiation Protection that reportedly contradicts repeated denials from scientists that power lines and electric appliances can cause disease in people. Ross Adey, chairman of the committee and a neurologist at the Veterans' Affairs Medical Center in Loma Linda, CA, reportedly claims there is a "powerful body of impressive evidence" that even very low exposure to electromagnetic radiation had subtle and long-term effects on people's health. Reuters quotes him as telling the magazine "the sensitivity of the brain and its mechanisms to these fields is the key," and said the report cited studies showing electromagnetic fields can disturb the production of the hormone melatonin, which affects sleep patterns and may help protect the bodies from degenerative diseases. The report recommended a safety limit of 0.2 microteslas, a very weak field compared to those generated by many household appliances and power lines. But, Reuters noted, "dozens of other reports have found no link between power lines or appliances and cancer." Coherent CW Announcement Long-time Coherent CW and BPSK advocate Bill de Carle, VE2IQ, announced two steps this month to encourage more activity in these modes. The updated Version 3.3 COHERENT software package is now available at no charge from Bill's computer bulletin board at (514) 226-7796. Download the file COHERENT.ZIP. **LATER NOTE: Version 4.1 is out, and is on the Longwave BBS! It is still named COHERENT.ZIP. Also download TUNER.ZIP, a useful helper file. The latest version now supports higher speed operation. The "MS50" command line parameter, for instance, specifies 50 milliseconds per signaling element, which equates to a CCW speed of 24 wpm, and a BPSK speed of 2 ASCII characters per second. If you are already operating BPSK, you may also want to get the file CLOCKSET.TXT (NOT on the Longwave BBS; only on Bill's), which explains how to adjust a parameter in the COHERENT program to compensate for clock frequency errors in your computer. And, Bill has reduced the price of the Sigma-Delta A/D converter kit. "To encourage more experimentation here's an offer that should be pretty hard to pass up: Complete kit of all parts needed to build one (1) Sigma-Delta interface (as described in Jan '92 QST) now only $49 plus $5 for airmail shipment. Kit includes one 3.5" diskette with the latest COHERENT (CCW / BPSK) and FFT (spectral display) software. Send US$54 to: Bill de Carle VE2IQ, 29 Sommet Vert, St-Adolphe d'Howard, P.Q. J0T 2B0, Canada." And Now, (What There Is of) The Mailbag... - Dave Hockaday (WB4IUY) and another nearby ham in eastern North Carolina, Kevin Leggett (KT4BN), are "just getting into this stuff and plan to put a couple of stations on, about 30 miles apart to QSO on...just for the fun of it. They'll probably run in the beacon mode when not in QSO ...maybe we'll be able to set up a schedule where we switch from beacon to transceive at a certain time daily. The plans now are for a cage vertical with tophat. Any input is welcomed!" BN will be located in Sims, NC, and IUY will be located near Youngsville. They have chosen a frequency of 166.66--- kHz. "Kevin has the exciter stage operational now. He built the modulator from the LCWA newsletter, and the power amp is next. I talked to a ham in New England yesterday who was an engineer for a company some years ago and had LW experience. He gave us some pointers on antenna loading that we're gonna give a try. This is really neat stuff, and we're looking forward to experimentation (on the air) really soon." Dave has two frequency selective voltmeters for sale, too. One is a Sierra 127C and the other is a Philco KS-15538, L5A. "They both cover 0 - 350 KHZ, have calibrated attenuators and receive signals down below -90 dbm, have 25 khz marker generators, headphone jack, and are battery powered. The Sierra 127C has a product detector and selectable USB/LSB modes, and an internal speaker. They are both in good working order. The Sierra is $65 and is very clean. The Philco is $40 and has a few scratches, but clean. Prices do not include shipping. Call (919)554-2154 home, (919)269-1190 work, or leave a message on the Longwave BBS." - Steve Ratzlaff (Palo Alto, CA; e-mail:Steve_Ratzlaff@smtp.svl.trw.com) checked in early last month. "Just back from 2 weeks in Oregon on vacation. Got in 11 VLF sessions. A geomagnetic storm over Sept 27-28 gave some fantastic listening. I will submit it to the INSPIRE Journal if it's not too late to get it in." Steve says he doesn't get to do VLF listening very often. "In my urban area there are no good sites nearby; I go to my folks' place in Oregon several times a year to do my primary listening there. Mike Mideke used to use my preamps in his big VLF loop and quiet listening environment. My spot in Oregon is only several miles from powerlines and hum is noticeable with a 130 foot circumference loop, but the sensitivity of a large loop is fantastic." - Lyle Koehler (LEK, MIN, K0LR; Aitkin, MN) reports: "I have several projects in the works with none making much visible progress. One thing I tried the other day was to modify my Autek RF-1 analyzer for use on LF. This was inspired by the MFJ-259 modification. I found that by replacing one of the inductors for another band with a 4.7 mH inductor, the RF-1 would operate over a range of about 140 to 290 kHz. Frequency indications were sometimes erratic and the L and C displays would give the same reading no matter what part was being tested. The Z and SWR displays worked over most of the usable range but became inaccurate when reading very low impedances. A 10-ohm resistor measured 8 ohms, and a 5-ohm resistor gave a zero indication on the display. I finally decided that it made more sense to build my own LF impedance meter if I really needed one, rather than risking destruction of the RF-1." "I'm hearing distant NDBs again at night. Noise levels have still been too high for reception of LowFER sky-wave signals. During the past month I've heard ART, BK, RM, SAM and 0KVL." - Will Payne (YWK, N4YWK; Crossroads, GA) says of the big storm: "The new 70 ft ham tower survived the storm. Regret not DXing while power was out. Station N4YWK is backed by 100 AH battery. Neighbors saw lights in my basement during blackout and asked if I get electricity from the big tower by my house." "The region below 9kHz is populated with artificial and natural signals, but information is mostly rumor and tips from friends. A system called SEAFARER on 76 Hz and a non-US system on 3 Hz using 2 Hz FSK (GMSK?). Also seem to recall proposed ELF system at 45(?) Hz using underground antennas which ran into strong public opposition. Was it ever built?" "Have built two new loops. The big loop is 12 turns 500 ft in circumference, using 6 pair phone wire lying on the ground, self resonant around 16 kHz. Other loop is 50 turns inside a 6 ft octagon of 3/4 cu pipe, using 25 pair telephone cable. Phone cable is a tight fit, a rat on a string and some liquid soap make the pull easier. Both loops seem adequately sensitive to 60 Hz, hi hi. The big loop is good for OMEGA, but lots of buzz. Have not yet mounted the shielded loop for hum rejection, but looks promising from infrasonic to at least 8 kHz. Working on some preamps/filters to make better use of these monsters, for reception of sferics and LOWFERs below 9kHz." "Have been talking with a nice geologist in Texas who uses ULF for oil exploration. They deploy miles long arrays of large search coils and drive a 200 amp 0.1 Hz square wave through the earth and record the step response in the coils. He told me 'another group on the west coast' had detected their signals. Have any LOWFERS detected these signals?" The geologist is looking for a sensitive magnetic antenna. "W4KIP, our local mad scientist, thinks an ultra high permeability flux gate would make the most sensitive receive antenna. A flux gate uses a bias coil to switch a ferromagnetic rod through saturation, and measures its switching point to detect magnetic fields. Supermalloy can be saturated just by laying it on a desktop facing north-south. W4KIP claims his first prototype exceeded all specifications but his customer found it unusable because they could not find many places far enough away from ferrous metal to operate the detector." Will is familiar with the Warm Springs area, having been one of the skydivers who used to frequent our local airport. In other electronic fields, he is active in ATV in the Atlanta area, at "UHF and RHF (Really High Freq.) Have good receive on 427.25 MHz fron new tower, soon to try 1253.00 MHz transmit. Built a pair of video transceivers last week on 2400 MHz, using a chipset from TriQuint. One is housed in an old modem case with a cute homemade quarter wave ground plane antenna just 1.2 inches tall. LowFERS would be green for an efficient antenna that size. Still ironing out the wrinkles but have already sent two way full motion color video across the basement. Our video link at 10260.0 MHz is near network quality thanks to improvements by W4KIP." - Robert Laney (RL) sent a correction for his beacon listing this month because, despite previous calculations, "the frequency counter sez 181.62 kHz." "I've wound an 8-inch diameter coil with Litz wire. The early measurements using the dummy load indicate about 30% more current for 1 watt in than the make-shift coil that I used last year. This is encouraging to say the least. Yesterday, the top hat for the antenna was put together. If our beautiful fall weather continues through this weekend, I may begin putting up the antenna." Footnotes. The fall weather truly has been beautiful around here. There's no telling what the winter may bring, but for now, those of us in this area have a lot to be thankful for. I hope you and your family have a joyful Thanksgiving as well. Hope to hear your news and comments this month, too. 73.