DL4YHF's Amateur Radio Software:
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Main Site: http://people.freenet.de/dl4yhf/spectra1.html Backup site: www.qsl.net/dl4yhf/spectra1.html ( Caution: severe bandwidth problems at qsl.net; and the old site at AOL has been removed due to access restrictions ) |
This program started as a simple FFT program running under DOS a long time
ago, but it is now a specialized audio analyzer, filter, frequency converter,
hum filter, data logger etc (see history at the bottom of this page). You can download
it from this site. Or look into the manual
though the manual included in the archive will be more up-to-date. If you are
looking for a short description in German language, look here
.
(SpecLab screenshot in "Colour Direction Finder" mode, VLF spectrum, colour~bearing)
Features
(screenshot of "Components" window)
Features which this analyzer does not have (but
others do...):
How to use Spectrum Lab to produce field strength plots of DI2AG, an experimental medium wave beacon on 440 kHz in southern Germany. It realizes some ideas we spoke about at the Ham Radio fair in Friedrichshafen (June 2005). More info in this document (up to now, in german language only) : Beschreibung des Einsatzes von Spectrum Lab als Bakenlogger für DI2AG.
There is a special narrow-band transmission mode in Spectrum Lab's "digimode terminal" called Chirped Hell, based on an idea by Markus, DF6NM. We used it on the amateur longwave band (136 kHz) to make some narrow band transmission. A special property of Markus' Chirped Hell principle is the relatively low crest factor, so it can be used to transmit characters (and even small images) quite effectively, but (unlike sequential multi-tone hell) you need a linear transmitter. An image received on a waterfall in "QRSS 3" mode may look like this:
If Chirped Hell signals are played much faster than in our experiments, they sound a bit like a melody as in this nonsense-example (you can play it with SL running in "fast morse-tape" mode to decode the HELL characters). Please turn your speaker's volume down before listening to this wonderful music ;-)
The installation package is divided into small pieces because my old internet connection failed quite often. There are several alternative sites with possibly better bandwidth, but not necessarily the latest "beta" version; see below.
For some stupid browsers, you may have to RIGHT-CLICK the following links to the zip-file and then select "save file.." (or similar) from a popup menu.
Because there were severe problems with QSL.NET recently, I had to
re-activate my "secondary site". The revision number and compilation date
of the latest Spectrum Lab version can be found at the top of this
document.
Because QSL.NET had serious bandwidth problems, the download from
my preliminary website at freenet.de may be
faster (it usually is).You won't be able to download SpecLab in a single file
because of a 1.5 MB-per-file limit at freenet (like their commercial says in
German: "Freenet - normal ist das nicht !". Anyway, they had a good bandwidth so
why complain if they are temporarily unavailable..). From the freenet site you
can download SpecLab split into two files :
If the freenet server does not respond (which happens occasianally), try this site which may contain the previous version - but beware, it is terribly slow, if the download works at all :
As an alternative, check the download section on Ko Versteeg's website .
How to
install SpecLab from these two files is explained here
.
The archive includes EXE-file, sample setting files, help system (in HTML
format) and a few other goodies.
Some additional utilities which may be useful:
To run some of SpecLab's companion programs (like the RDF
calculator, but not for SpecLab itself), you may have to download Borland's
VCL40.BPL from this link. It's quite large (1.9 MB unpacked), so I threw it
out of the application package. After downloading the file, unzip it and copy
VCL40.BPL to your windows system directory (c:\windows\system for
example) or into the directory of the application which needs it.
Note:
The link may be temporarily unavaible due to cancelled AOL membership !
If you want to write your own program to control Spectrum Lab, read this document which explains how to communicate with it using simple WM_COPYDATA messages.
There's a lot of other very nice sound analyzers elsewhere, but once upon a time (when there weren't so many out there) I decided to convert my old FFT audio analyzer from DOS to Windows ... see oldest entry in the history below). Some info about the revision history can be found in the file REVISION.TXT after unzipping the downloaded archive.
2005..
August: The radio-direction finder can now suppress noise from up
to three independent directions, and a new spectrum-event-logging feature was
added (right-click into the waterfall to see it).
July: Wrote a highly
experimental "output plugin" for Winamp, to feed audio streams from the internet
into Spectrum Lab.
June: Some modifications, bugfixes, and a description how
to set up SpecLab as a beacon monitor/logger for DI2AG
.
January 2004:
Added an optional quadrature output for certain digimodes
(QRSS, PSK, MSK) to support a simple, sideband-rejecting RF modulator (using the
"phasing method", without the need to build a 90° audio phase shifter which is
often the most complicated part of such a transmitter).
December
2004:
Started a few experiments with MSK (minimum shift keying), first using
an incoherent demodulator, next step will be a coherent demodulator ("de Buda"
or "Massey/Hodgart" for example). The advantage of this modulation technique is,
there is no envelope shaping involved, so you don't need a linear transmitter to
send it. However it is very questionable if MSK will ever be a popular mode like
PSK31 in the amateur radio community. More on this in the
manual...
Furthermore: New "conditional action" tab, which is useful for
certain applications like counting meteors, etc... ;-)
May-October 2004:
Finally bought an Audigy 2 ZS myself, to play a bit with
"true" 96 kHz sampling (for ADC+DAC), and -possibly- with 24 bit resolution. I
still don't know why they need 24 bits to achieve an SNR or 108 dB, but that's
another story. Futhermore: Automatic gain control in the DSP blackbox, an
external trigger for the waterfall, and a few new display units (volts, watts,
dBm, dBV). Averaging now calculated on voltages or powers, but now on
logarithmic scales (which gave no meaningful "dB"-results). Furthermore:
Published the method to control SpecLab from other programs using a simple message-based
protocol.
Jan.-Apr. 2004:
Logarithmic frequency scale, modified PSK demodulator,
modified noiseblanker, minor bugfixes. Someone reported SMPORT (the port
access driver) caused problems under WinXP - effect not reproducable yet
!
Got the info that the ADC in my Soundblaster Extigy does NOT support
sampling at 96 kHz - I shouldn't have trusted the label on the box :-( ... but
help is on the way: SpecLab works well at 96kHz with the Soundblaster
Audigy 2 ZS card - thanks for the report, Arthur.
Nov.-Dec 2003:
V2.3
New functions: Filter with FFT convolution, for extra-long FIR filters,
denoiser (using spectral subtraction), and a brute-force autonotch for VLF
listening. Optional peak-detecting amplitude bar which runs parallel to the
spectrogram. New function for SINAD measurements.
October 2003: V2.2
Minor changes and bugfixes. Tolerance range for the
soundcard's "calibrated" against the "nominal" sampling rate is now +/- 250Hz
(was +/- 100Hz) because some devices seem to run at 5400 Hz instead of 5512 Hz.
Azimuth calculation of very weak signals improved. Cursor display now
alternatively in menu line, if the controls on left side are invisible.
August-September 2003:
More steps towards a full implementation of DF6NM's
Wideband Direction Finder with Colour Encoded Spectrogram Display in
Spectrum Lab. For VLF enthusiasts, there is the option "two loops without an
E-field antenna" which does not require a broadband 90° combiner. A nulling
cardioid can be used to cancel noise from a certain compass direction. The
description of an experimental VLF radio direction setup can be found here
.
July 2003:
Increased the maximum waterfall scroll/update rate. Up to one
pixel strip per millisecond is possible, if your PC is fast enough. Best in
"non-scrolling" mode (like in the prepared "Tweek/Sferics" mode).
May 2003:
Minor changes in the "plotter" window, can be scrolled back and
forth along the time scale. Used for long-term observations (like the "VLF
station plotter" which plots the field strength of a number of european VLF
transmitters over time). Added some usr-files for ELF/VLF monitoring.
February - March 2003:
Implemented Paul Nicholson's multi-stage hum filter
in SpecLab's DSP blackboxes. This specialized comb filter can remove hum (and
harmonics) without seriously degrading the audio quality. The current
implementation is based on Paul's "C" sourcecode for Humfilt-1.2, it was
available on his website.
December 2002:
Spectrum Analyzer runs in "stereo" mode now. The border
around the "Watch List / Plot Window" can be turned off. A lot of internal
modifications, may have added more bugs... the programs seems to remain a
building site. Many of the new functions are not mentioned in the manual yet !
October 2002:
SpectrumLab now supports 'any possible sampling rate', which
was necessary for an external PIC12F675-based A/D converter connected to the
serial port (2 channels, 12 bits/sample, 2500 samples/second). Also fixed some
bugs in the export function (last definition line was ignored) and the analysis
and playback of stereo audio files.
June-July 2002:
SpectrumLab can now use the simple file-based "sound
utility" interface described in another
document. This makes it easy to write simple drivers in any language for
external A/D-converters, etc. Even a BASIC program running in a DOS box should
work. And: split frequency axis, effective voltmeter ("veff"-function in the
interpreter), improved file analysis features.
September 2000:
Project was renamed to "Spectrum Lab" (or short SpecLab)
because the program can do more than just analyze audio input. Meanwhile it can
also be used for some 'special' digital communication modes used by radio
amateurs on longwave. <part of the history removed, got too
long>
Early 2000: Started to convert my old spectrum analyzer for DOS
into a windoze program, because the required drivers for soundcard and SVGA card
were not available any more. Now the program requires a quite fast PC (a
133-MHz-Pentium or better), crashes under certain conditions (slow CPU), and
requires some strange DLLs. The graphics mode should be at least 800*600 pixels
with 256 colors (true color required for Colour Direction Finder). The program
once ran on an old 90MHz-Pentium with 640*480 pixel display if not too many DSP
functions are active on the same time.