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PA3BBR > VLF 27.08.96 19:06l 746 Lines 31565 Bytes #-10915 (0) @ WW
BID : 39289_PI8VAD
Read: DL5MAV GUEST
Subj: VLF-listeners (2).
Path: DB0KCP<DB0MWS<DB0RBS<DB0PSC<DB0ACH<DB0ACC<PI8DRS<PI8DAZ<PI8APD<PI8GCB<
PI8WFL<PI8VNW<PI8VAD
Sent: 960824/1714Z @:PI8VAD.#ZH2.NLD.EU #:39289 [Dordrecht] $:39289_PI8VAD
From: PA3BBR@PI8VAD.#ZH2.NLD.EU
To : VLF@WW
Hello VLF-interested ham's.
I did receive several reactions. Therefor I will distribute the information
already distributed earlier in the net by this bulletin and not personal.
I did build a receiver BBB-4 but made a little modification of the front-end.
This was neccesary since the JFET was difficult to get. Instead I used a BF960
Dual-Gate MOS-FET which has good IM-rejection.
I think any such FET will do as long it has a high performance.
Hereby is my front-end in poor-mans-graphics (hi):
----------------------------------------+9V
| | |
| --- 1uF \
/ --- / 1k5
\ |g2 \
P1 /<----|| d|-----> See BBB-4 Schematic.
\ |---|
( ant) / | bf960
o-/\/\/--------\|/----||---|
1M | | | g1 s|
| / | /
--- \ | \ R (270)
--- /10| /
47p| |M | |
--------------------------------------------- - Ground.
With P1 you can vary the drain-current to find the optimum point for the
best results. My version, wired point to point, tends to generate when the gain
is too high. Reason for that that is my headphones has no shielded cord as I
did not expect! Grounding of the receiver is neccesary, otherwise it will
generate as well.
Now hereby the bulletin of N6NKS and other info which i got from
the db0mwx-bbs.
I hope to hear from any results.
'73 de Edwin pa3bbr@pi8vad
----------------------------------------------------------
VLF @DL de:DB1QW 19.06.96 15:09 60 662 Bytes
natural radio info
*** Bulletin-ID: 19660ADB0SGL ***
960619/1503z DB0IZ , 960619/1600z DB0QS , 960619/1351z DB0HSK
960619/1440z DB0SGL
de DB1QW @ DB0SGL.#NRW.DEU.EU (Wolfgang)
to VLF @ DL
RX fuer Whistler, Sferics, etc. im Bereich bis ca 11KHz, brauchbare Ergebnisse
allerdings nur mindestens 2 Km von jeglichem man-made noise entfernt.
Demnaechst einige Empfangsergebnisse als .wav Files.
Gruss aus Eitorf
Wolfgang
VLF @DL de:DB1QW 23.06.96 23:42 60 20736 Bytes
natural radio neueinspielung
*** Bulletin-ID: 236612DB0SGL ***
960623/2336z DB0LJ , 960623/2307z DB0SGL
de DB1QW @ DB0SGL.#NRW.DEU.EU (Wolfgang)
to VLF @ DL
REPOST NOTE!: Capacitor values for C4 and C5 have been corrected! They were
incorrectly 0.047 uF (47 nF), BUT SHOULD BE: 0.0047 uF (4.7 nF).
There was a related 3-part article to this posting, entitled VLF STORY.
originally posted to rec.radio.shortwave 59300-59302 in August 1995.
Re-post note: By this time, those have been archived and are
no longer currently available on the rec.radio.shortwave
USENET group for reading. Please e-mail me if you desire the text of
this article, and I'll send it along to you.
(Editor's note: VLFSTORY.ZIP, containing the entire contents, is
available on the Longwave BBS, or at the following FTP sites:
users.aol.com:/lwcanews/naturadio
ftp.uni-wuppertal.de:/pub/pc/lowfer/lwbbs/naturadio)
Also, note the WWW URL toward the end of this posting for WAV file
availability. I noticed I misspelled the WWW URL, so here it is--
correct at last: http://www-pw.physics.uiowa.edu/mcgreevy/
This URL will be repeated at the end of this posting.
--------------------------------------------------------------------
Use a fixed/mono-width font such as courier 10 cpi or "line Printer"
if viewing in graphical editor/word-processor,
or use Windows Notepad or a DOS text editor such as edit.com.
Thanks to everyone's nice comments! Due to many requests, here is
the schematic to the McGreevy BBB-4 ELF/VLF "whistler" receiver:
REVISED 15 DEC. 1995, WITH LINE-NUMBERS INSERTED IN SCHEMATIC AREA
AND ALSO DUE TO A PART BEING LEFT OUT & INCORRECT PART VALUES (C4, C5)!
-----------------------------------------------------------------------
S. P. McGreevy BBB-4 Naturally-Occurring V.L.F. Phenomena E-field
Receiver ("Whistler Receiver") For Broadband 0.2 to 11 kHz Reception
of naturally-occurring radio phenomena.
(Originally copyright 1993 S. P. McGreevy). spmcgrvy@ix.netcom.com
Snail: Steve McGreevy, 45 Elda Drive, San Rafael, CA 94903-3723, U.S.A.
REVISED ASCII SCHEMATIC OF McGREEVY BBB-4 ELF/VLF RECEIVER w/LINE #'S:
(Sorry about the ascii text "graphics" -- I'm not too good
at doing schematics using text characters, but I wanted this to
be fully compatible with the text-only nature of USENET, etc.
NOTE: I've added line numbers to aid with "fixing" any scrambled lines:
These numbers are at the BEGINNING of each line in schematic (01 to 72).
--------------------------------------------------------------------------
01) __________ o +9 Volts
02) \ | / |
03) \ | / ___________________|_____________\ To Audio
04) \ | / C9 + | |0.1uF | / amp. 9 v
05) \ |/ 100uF __|__ __|__ C10 | rail.
06) \/ _____ _____ |
07) | | | \
08) 1 to | |__________| / 4.7K
09) 3 mtr.| __|__ \ R4
10) whip | R1 C1 / / / 2N5484 /
11) ant. | 1 Meg. 0.1uF Q1 D |_______||____\ To filter &
12) | G |_____| || / A.F. AMP.
13) |---/\/\/\---||---|-----|-------| 0.1 uF
14) | | |-----| C3
15) C2 _|_ \ S |
16) 47pF ___ / R2 /
17) | \ 10 Meg. \
18) | / / 1K
19) | | \ R3
20) |-----| /
21) __|__ __|__
22) / / / / / /
23)
24)-------------------------------------------------------------------------
25) AUDIO FILTER
26) * (^^^ = coil windings)
27) From FET drain coupling L1 (xfmr pri.) or 180-200 mH choke
28) cap. ==============
29) \_____ _________|^^^^^^|^^^^^^ To input of
30) / | |_______________| |____\ bi-polar
31) | | | | / audio amp.
32) | .0047 uF | 0.1 uF
33) __|__ C4 .0047 uF | C6
34) _____ C5 __|__
35) | _____
36) | |
37) | |
38) __|__ __|__
39) / / / / / /
40)
41)
42) * L1 is a 1 KCT pri. to 8 ohm sec. audio xfmr. using one end of primary
43) winding and the center-tap as a series inductor equalling approx 160 mH.
44)
45)-------------------------------------------------------------------------
46) MIC. LEVEL NPN AUDIO AMPLIFIER
47) (+9 volt rail)
48) \__________________________________
49) / | |
50) | 10 K /
51) 33 K \ R7 \
52) R5 / / MIC. LEVEL
53) \ C ____|______| |_______\ OUTPUT
54) From audio / / | | / To tape rec. or
55) filter | B | / 0.1 uF speaker amp.
56) \________________|_________|/ C8
57) / | |\__
58) | Q2 | \/ E
59) | 2N3904 \______
60) | NPN | |
61) | Bipolar + | |
62) | Transistor __|__ \
63) \ 1uF _____ / R8
64) 4.7K / C7 | \ 1.5K
65) R6 \ | /
66) / |_____|
67) | |
68) __|__ __|__
69) / / / / / /
70)
71)
72)-------------------------------------------------------------------------
The "BBB-4" is a broadband 0.2 to 11 kHz V.L.F. receiver with a
passband peak at approximately 2 kHz, and is designed to receive
naturally-occurring V.L.F. phenomena (such as "whistlers") that occur as
electromagnetic (radio) waves at audio-frequencies. This receiver was
designed to be hand-held, and its output patched to a microphone-level input
such as a tape-recorder or speaker-amplifier (such as the one available at
Radio Shack ("Mini Audio Amplifier/Speaker" cat. # 277-1008).
Dissatisfied with more complicated and cumbersome multi-turn loop receiver
schemes, I opted to design a whistler receiver which was simple to build and
use, but was as sensitive and low-noise as possible while being highly-
immune to broadcast station overload.
The BBB-4 V.L.F. receiver circuit ("BBB-4" standing for a fourth
version of my "Bare-Bones-Basic" designs) is remarkably sensitive and
works very well with short whip antennas between 30-60 inches in length,
since it operates on the same principle as high-impedance "active antennas"
designed for other frequency ranges (such as long, medium or shortwaves).
The BBB-4, due to its F.E.T. "front-end" being a high-performance J-FET,
has an input impedance of about 10 megohms, which is why the short whip
antenna--more correctly called an "electrical-field probe"--works fantastically
for being such a tiny fraction of the received-frequencies' wavelengths in
size (the ultimate isotropic antenna).
R1 and C2 act as a roll-off to frequencies above about 20 kHz,
efficiently eliminating potential receiver overload/intermod from Loran-C
(100 kHz), strong AM-BCB signals or SWBC signals, and frequencies up
into the VHF ranges. R2 sets the gate impedance for the J-FET. R4 and R3
set the optimum bias on the FET for maximum dynamic range and minimum
susceptibility to overload and intermod. C3 and C6 slightly helps roll-off
low-frequencies such as powerline "hum." The "pi-filter" consisting of C4,
L1 and C5 roll-off frequencies beginning at about 7 kHz, so there are not
excessive levels of 10.2 - 13.6 kHz "Omega" signals or higher frequency
signals, which can create problems with the recording system connected to
the output of the receiver. R5 to R8 , Q2 and C7 form a fairly low-noise
Class-A audio amplifier which boosts the output from Q1 to a level plenty for
all microphone-level recorder inputs and even some more "sensitive" line-
level inputs. Bypassing R3 (1K) with a 2.2 uF cap will boost FET gain
somewhat, esp. the higher frequencies--depending on your location
and listening conditions, this may or may not be desireable.
The circuit can be built on perfboard such as IC-LSI boards or even
wired point-to-point, as layout is not very critical. However, the parts'
values ARE critical for optimum passband shape and sensitivity. L1, the
inductor, can either be a 160-200 mH choke or the Radio-Shack 1K to 8 ohm audio
transformer available at Radio-Shack (cat. # 273-1380). Use the black and
green or black and blue wires (the center-tap and one end of the primary
winding). The audio transformer was used since it is easily available at
Radio Shack stores. In fact, ALL the parts with the exception of the 2N5484
FET are available at Radio Shack. Very good performance (but slightly
reduced gain) can also be had if a 2N3819 J-FET, available at Radio Shack,
is used. If so, R3 must be 220 ohm and R4 must be 1K, because the 2N3819
needs different biasing than the 2N5484. Also, if you use the Radio Shack
2N3819 FET, you might wish to reduce C4 and C5 to .033 mF, since there
will be less high audio-frequency output from the 2N3819. Keep C4 and C5
.047 mF if you live in Hawaii or within 300 miles of La Moure, ND (south-
eastern North Dakota) due to the Omega-navigation transmitters (frequency
stepping from 10.2 to 13.6 kHz) being located there. Capacitors C4 and C5
work with L1 to reduce Omega to tolerable levels. Solder the J-FET into the
circuit LAST, and take measures to protect the FET from static electricity.
The total cost for parts (not including an enclosure) for the BBB-4 are in the
neighborhood of $15-20 U.S. A rugged telescoping-whip antenna is the GROVE
ENTERPRISES "ANT-8" 7-46-inch telescoping whip with a BNC
connector. This is available for $16.95 from Grove Enterprises, P.O. Box 98,
Brasstown, NC 28902-0098, U.S.A. (Order Line 1 (800) 438-8155. They
send out a free catalog.
Another telescoping whip antenna of like design is
available from C. CRANE RADIO CO. in Fortuna, CA in Fortuna,
California (800) 522-TUNE (522-8863). E-field-probe receivers of this type
need to be operated at locations away from trees, buildings, or other
obstacles by about 100 feet/30 meters. This is because received
signal levels (due to E-field attenuation) will be poor if the receiver is
operated too near (or under) such obstructions.
The greatest nemesis to monitoring and recording naturally occurring
VLF phenomena are electric a.c. powerlines, which emit annoying hum at
50/60 Hertz and also harmonics beyond 3 kHz. The only cure for this "hum"
problem it to locate monitoring sites well away from a.c. powerlines.
Locations at least 1/2 mile/1 km or so away from a.c. powerlines will begin
to be acceptable, though the farther you can get from powerlines, the better.
Hilly or mountainous terrain (with open areas free of trees) offer larger areas
away from powerlines, though large fields and meadows where the
powerlines are shielded by trees, etc. may be surprisingly hum-free. Remote
locations such as deep into desert and wilderness regions offer the most
rewarding locations, both aesthetically and electrically, to listen, and you may
be able to get over 10 miles from the nearest powerline. If so, you can make
the receiver's antenna several meters in length (keeping it vertical) for
maximum sensitivity. Longer vertical antennas or horizontal wires may
either overload the receiver, or in the case of long/low wires, will create a
mismatch which will actually reduce output. Experiment here.
NOTE: A 100 mH choke across C5 (th secone .47 cap in the audio filter
will greatly reduce the below-1 kHz frequencies, including pesky power-
line hum. This may enable you to listen far closer to AC power-lines
including even some backyard locations!
Grounding is non-critical. High-impedance FET receivers of this type
need only minimal grounding to work well_even just the body of the listener
holding the metal enclosure of the receiver will be adequate in most cases. If
recording, it is best to stick a 8-10 inch ground rod into the soil to reduce the
possibility of feedback with some tape recorders. Also, a small ground-rod
(8-10 inches long) will cut noise from body or foot movements (due to
capacitive interaction with the ground). If you ground the receiver to objects
such as fences, beware that certain grounds may couple a.c. powerline noise
to the receiver, which is why I recommend a simple Earth ground.
Better quality tape recorders, with adjustable input level controls, are
desirable, as "cheapie" portable recorders with auto-level control will often
have annoying variations in record level due to lightning-sferics. And, these
cheap recorders also put noise of their own onto the tape. A shielded 600 ohm
patch-cord will suffice between the output of the BBB-4 and microphone
input of a tape recorder.
The most common naturally occurring V.L.F. emissions to be heard
are the myriad "crackling and popping" sounds of lightning-stroke
electromagnetic impulses from lightning storms within a couple thousand-
mile radius of the listener. Since there are nearly 100 lightning storms in
progress anywhere on the Earth at any given time, and that millions of
lightning strokes happen daily, there is never a moment when these lightning
"sferics" will not be heard. However, the density and strength of lightning
sferics can vary day-to-day and hour-to-hour. Mid-winter offers the lowest
density of sferics, and summer evenings can be full of a dense barrage of
strong sferics.
The other most common (and most awesome) sounds are "whistlers"_eerie
descending tones caused when the lightning electromagnetic energy gets
"ducted" along Earth's magnetic lines-of-force (magnetosphere) to the
opposite polar hemisphere, then gets rebounded back to the vicinity of the
originating lightning stroke impulse. However, there doesn't have to be
lightning within sight or even a few hundred miles of your listening
location_lightning from storms up to thousands of miles away, particularly if
more to the north of your location, can generate large whistlers which are
heard continent-wide. On the other hand, it's quite spectacular to watch
distant lightning storms generate whistlers in the receiver's output_you hear
the huge "crack" of the lightning impulse sferic, then, if the conditions to
support whistlers are occurring, a whistler may follow from 1 to 2 seconds
after the lightning stroke.
Optimum times to listen for natural V.L.F. phenomena, such as
whistlers, are between sunset and sunrise, with the midnight to sunrise period
generally being the best. Statistically, the greatest activity to be heard is
around dawn and sunrise (4-7 a.m. local time)_sferics tend to be fairly low as
compared to the sunset period.
Dawn Chorus can occur during magnetic-
storms, and will peak anywhere from an hour before sunrise to 2 hours past
sunrise. Whistlers can occur at anytime, but the period of minimum
frequency is midday. Sometimes, activity can also occur just after sunset,
but sferics will be fiercer. Lightning sferics will be most fierce during
summer afternoons and minimum (generally) an hour or so after sunrise until
thunderstorm activity picks up later on. Winter can present delightfully low
lightning sferics_other activity will be more "in the clear."
Tweeks, the "ringing/pinging" sounds of sferics caused by the Earth-
surface/ionosphere "waveguide," will be best from an hour after sunset to 2-3
a.m. local time, gradually tapering off toward sunrise. Their number and
intensity of "pinginess" can vary from night to night_some nights they can
sound rather "pale," but other nights they can ring in a variety of beautiful
mixtures and pitches. Whistlers, which may or may not be heard on some
days or even weeks, can range in sound from quite pure notes to very diffuse
"breathy" sounds. They can swoop in frequency from very high to low, or
abruptly cut-off as they descend in pitch.
Don't be discouraged if you listen for several hours, or several sessions on
different days, without hearing whistlers or other natural radio phenomena.
When you DO hear them, it will make up for the "dry" times, as there is
nothing like "live" listening!
Listeners located north between 40-55 degrees north or south latitude
are in the optimum latitudes for monitoring natural V.L.F. phenomena. If
you can see visible Aurora (Northern/Southern Lights) from your location,
you are at a great location for natural V.L.F phenomena monitoring!
Latitudes between 20-30 degrees north and south will hear less, but at times,
still loud phenomena. I've heard whistlers just fine in Hawaii_presumably
those whistlers were louder farther north, but still, they were heard!
DO NOT operate this receiver (or any other) when nearby lightning
threatens! Take appropriate lightning precautions when lightning is
occurring nearby (within 5-10 miles). Nearby lightning will cause
excessively loud sferics in the receiver's output, and whistlers will not be
louder just because lightning is close-by. Reserve listening for fair weather
periods_most often, the best and loudest natural V.L.F. phenomena will
happen during clear weather, since lightning can be quite distant, as
mentioned above, and still spawn loud whistlers.
If you would like to purchase a ready-made receiver which is
fashioned like a "Walkman-style" whistler receiver, e-mail me for
details. I don't want to "advertise" here.
The Longwave Club of America also has other designs of ELF/VLF "whistler"
receivers, and has a BBS run by member John Davis. The LWCA BBS is at
(706) 672-0360 with speeds up to 9600 (8,N,1). Download the
ALLFILES.TXT or ALLFILES.ZIP for listing of files avail on this BBS.
A WWW URL of natural radio WAV files (most 8 bit/11 kHz sampling
compatible with Windows "speaker.drv" as well as 8-bit sound cards, plus a
few 16-bit files for 16-bit sound cards are available for downloading at:
http://www-pw.physics.uiowa.edu/mcgreevy/
Special thanks to Larry Granroth a the U. of Iowa for doing this for me!
Coordinated monitoring of naturally occurring V.L.F. phenomena
among individuals and groups has a strong potential to uncover new and
previously unknown characteristics of these phenomena, particularly if those
monitoring simultaneously are located hundreds and thousands of miles
apart. Research and understanding of V.L.F. phenomena has been hindered
by a lack of listeners, which is something a few research groups, both
amateur and professional, are attempting to alleviate.
I hope you enjoy this rcvr. and are interested in monitoring and
studying naturally occurring VLF radio phenomena for yourself. It is quite
fascinating, especially when one ponders the fact that Earth's natural radio
emissions have been "sounding-off" way before we Humans came into
existence and started making radio waves of our own! Happy Listening!
Stephen P. McGreevy
Originally released November 1993, updated November 1995
Additional Tips:
1) A 100-200 mH inductor connected across C5 the will act as a
high-pass filter, nicely attenuating 60-360 Hz powerline emissions (hum).
2) If you want less gain from the Q2 stage (and slightly lower noise),
reduce R8
to 4.7K.
3) Listen to WWV-shortwave (2.5, 5, 10, 15, 20 MHz) for geo-
magnetic indices at 18 min. past each hour (WWVH-Hawaii at :45). A K-
index at or above 3 indicates enhanced conditions for natural phenomena,
especially chorus.
73,
Stephen P. McGreevy, N6NKS
----
Zum Testen des Programm GRAM22 sind folgende WAV Dateien bei mir
erhaeltlich:
( man kann sie natuerlich auch selber im Internet abrufen >300 kByte )
VLF1.ZIP GUIDE TO FILES CONTAINED IN THIS ZIP FILE:
---------------------------------------------------
All Natural Radio recordings were recorded by Stephen P. McGreevy
using the McGreevy WR-4B E-Field VLF receiver and 10' (3 meter)
vertical antenna. Tape recorder used was a Marantz PMD 212.
Files were converted to .WAV files using a SoundBlaster 16
card and Wave 'OLE or WaveEditor. The following files were
recorded at 8 bit, 11 kHz sampling rate. (The antenna and front-
end circuit of the WR-4B whistler receiver was temporarily attached
to my van via bungee cord) and the control box sits next to beds in back.
1) HUGH_WHI.WAV Huge whistler (very strong), moderate diffusion
7.5 sec. recorded 17 Sept. 1993 20 mi. west of Wendover,
NV at around 6:30 am PDT (1330 UTC).
2) LOUD_WHI.WAV Another strong whistler, same location as above
8.5 sec. within 10 minutes of the other one. Initiating
sferic "tweek" clearly obvious!
3) LOUDWHI2.WAV VERY LOUD Mod. diffusion whistler with weak
9 sec. diffuse echo accompanied by triggered emissions
at time of whistler.
4) PURENVWH.WAV 04 June 1993, 60 miles NNE of Reno, NV, 1430
19.5 sec. UTC, 7:30 am PDT. Weak Dawn Chours (minor
mag. storm in progress with weak background
layer of sferics plus very strong sferics
from lightning within 100 mi. of receiver.
A strong, pure whistler of slow descending
rate occurrs after one of these semi-
local lightning sferics.
5) WHIS4194.WAV 01 April 1994, 1130 UT/0330 PST, 100 mi. north
of San Francisco, CA in Mendocino Co. (Fish
12.5 sec. Rock Road 20 mi. west of Ukiah). Clusters
of nearly pure whistlers occurred all night
and were quite beautiful! This segment has
2 strong and 2 very weak whistler.
Natural Radio emissions such as these occur in the 0.1 to 11 kHz radio
spectrum--essentially, they are audio-frequency radio waves! This is
just a small variety of fascinating "sounds" to be received at these
ELF/VLF frequencies. You must be located at least 1 to 2 miles from
any power-lines so their "hum" is not received. This is why I like
to listen in the NV high-desert and Great Basin Area--plenty of open
spaces!
A hand held version of the WR-4B is available for $105. Contact
Steve McGreevy at: S.P. McGreevy Productions, 45 Elda Drive, San
Rafael, CA 94903. E-mail: spmcgrvy@ix.netcom.com -- or --
s.mcgreevy@genie.geis.com
73 de Rue ( DJ4KI @ DB0BOX )
---
From: G0RTX@HB9IAP.SROM.CHE.EU
To : VLF@WW
topfiles.txt 12/03/95
The LWCANews ftp site contains files relating to longwave radio
monitoring, natural radio research, and longwave and medium wave low power
experimental operation (under FCC Part 15 and equivalent Canadian rules).
These are some of the topics of interest to members of the Longwave Club
of America, covered in the club's monthly journal, The LOWDOWN.
These files have been gleaned from the Longwave/Part 15 Bulletin
Board System. Because of size limits on this ftp server, we can only
include a limited sample of the BBS library here. There is no charge for
using the BBS, other than the telephone call. The details: 8-N-1, up to
9600 baud. The number is 706.672.0360.
Program files are mainly for PC-compatibles since we don't have the
means to test other kinds. However, we try to make text and picture files
as widely useful as possible. (Some improvement remains possible here.)
DOWNLOADING: Remember, this ftp server follows Unix procedures. Among
other things, this means directories and filenames are case sensitive. We
have named all files on this server in _lower case_ letters, so if you see
a file listed below in upper case, that's accidental.
This listing contains the filename, size in bytes, the date the file
was uploaded, and a brief description. Here they are, by directory:
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
/0read
topfiles.txt ~6,515 12/03/95 This file.
whatisit.txt 4,294 12/03/95 What are these LowFERs, MedFERs and Part 15?
lwcainfo.txt 2,553 12/03/95 Info on LWCA and its journal, The LOWDOWN.
more-net.txt (coming soon) A file listing other LF-related resources
available on the Internet.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
/longwave
notebk33.txt 25,226 12/03/95 "LF Notebook" column #33, Dec. 95 LOWDOWN.
Contains news of LF amateur band effort, coherent CW and BPSK.
z2-in-hi.zip 138,391 12/03/95 Steve McGreevy's record-setting reception of
Michael Mideke's former LOWfer beacon Z2 on 165.7 kHz, as recorded
on Kauai, Hawaii, Jan. 16, 1986. A 27-second WAV file and
explanatory text file. PKZip 1.10
LIFTED FROM THE INTERNET BY G0RTX@HB9IAP.SROM.CHE.EU.
arlb036.txt 3,213 12/03/95 NTIA report cites new spectrum prospects for
the amateur service, including 160-190 kHz. From ARRL, April 95.
lfmfbcns.txt 20,229 12/03/95 Comprehensive list of reported active Part 15
beacons, both LF (updated thru 11/17) and MF (thru 11/19),
plus the preliminary state-by-state operator contact list.
lf-loops.zip 47,514 12/03/95 Article on remotely tuned LF receiving loops
by K0LR. Windows Write document w/pix. PKZ 1.10 Feb. 95 LOWDOWN.
hooploop.zip 52,067 12/03/95 John Hoopes' article on the Hoop Loop LF re-
ceiving antenna, Dec. 1992 LOWDOWN; .TXT and .PCX file; 281K unzipped.
vlf_elf_.txt 2,264 12/02/95 Brief bibliography of LF-related topics. From
Michael Stein, UCLA, via Internet.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
/medfer
part15_s.txt 38,468 12/03/95 Part 15 Federal Communications Commission
rules governing unlicensed low power transmissions. This is
an abridged version covering only the most relevant sections for
home experimenters. Prepared September, 1994, but these sections
have not changed since. Both longwave and mediumwave.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
/naturadio
whistler.zip 21,282 12/03/95 John Davis' IC-based whistler receiver
design; text and two .pcx illustrations. 40K unzipped.
whistler.txt 4,902 " :
whisrec.gif 16,866 " : -- Individual files from above, available
whismod.gif 10,888 " : separately, images converted to GIF.
vlfstory.zip 30,539 12/03/95 "A VLF Listener's Story" by Steve McGreevy,
an exciting account of Natural Radio monitoring, encompassing
whistlers, auroral emissions, red sprites and other mysteries
of VLF. Explains fundamentals of whistler receivers and antennas.
bbb4rx3.txt 18,946 12/03/95 Details of Steve's BBB-4 E-field receiver. Use
Notepad, MS-DOS Editor, or other editor with monospace font,
to be able to view "text schematic" properly.
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/programs
coherent.zip 55,296 12/03/95 The COHERENT software package by VE2IQ, for
CCW, BPSK and other advanced communication modes. Version 4.4,
Nov. 11, 1995. DOS. Includes lattice-coded PSK. Free.
gram23.zip 33,408 12/01/95 Audio spectrogram program for Windows, capable
of moderately sophisticated spectrographic analysis of digitized
audio (WAV files). Displays on-screen and saves BMP images of
the display, which you can print through Paintbrush or other
graphic utilities. Handy for whistler hunters! By R. S. Horne.
Free distribution. (Ver 2.3 fixes BMP problems some users had.)
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/tech
lattice.txt 7,580 12/03/95 From VE2IQ. Explanation of lattice coding, a
technique for improving Phase Shift Keying error rate.
dsp59mod.zip 61,952 12/03/95 From K0LR. Unzips to 474k Windows Write file
with illustrations. Modification to Timewave DSP-59+ digital
signal processing filter; external oscillator allows lower CW
center freq, makes center freq tunable, narrows bandwidth. Dec. 95 LOWDOWN.
unipre1.zip 202,112 12/03/95 Universal LF/MF antenna preamplifier by K0LR,
updated version from Aug. 95 LOWDOWN. Works with loop or whip
antennas, LF or MF. Windows Write document with schematic. Note:
picture may be clearer if you have CorelDraw installed.
gnd_isol.zip 31,320 12/03/95 Jim Hagan's article (.txt) and schematics
(.pcx) on isolating remote antenna preamps from ground loop
noise pickup. PKZip 2.04. 240 kbytes expanded.
-------------- End info ---------------------------------------------------
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