[Lowfer] Re: Who pioneered QRSS?

[Alberto di Bene]

"John Davis" <longwave@mindspring.com> wrote :

  > Maybe some of the actual parties involved will be able to fill in more
  > details.  I'm sure Alberto has clearer and more authoritative memories of
  > the events leading up to his own work, for instance.
  >
  >

What I recall is the following:   (warning, long append)

In 1997 I went to an EME conference in Tuscany, Italy, where I saw the
FFTDSP program by Mike Cook AF9Y. About in that time frame I was doing
my first timid attempts to program under Windows.
I sent the registration money to Mike for my copy of FFTDSP (yes, you
had to pay for it) and played a little with it. I decided to try to write
something similar, using some FFT routines I had handy at that time.
But those routines were meant for the 16-bit DOS world.
So my first attempt was HAMVIEW, co-authored by Vittorio IK2CZL, a DOS
program written in C language. HAMVIEW had the same limitation of FFTDSP
of having a fixed FFT bin size of 2 Hz, not quite right for QRSS.
But at that time QRSS meant nothing to me.
Moreover, as HAMVIEW did talk directly to the sound card hardware,
setting DMA buffers, hooking interrupts and so on, it was very dependent
on the type of sound card used.
Actually it worked only with the Creative SB16 ISA card, and its close
relatives, like the AWE32 and AWE64. Same limitation as FFTDSP.

In 1999 Vittorio and I started to think about a Windows version. We
initially named it Winham, but then we preferred the name Spectran
(for Spectrum Analyzer). We were  warned that Spectran was a registered
trade mark for a kind of nylon fiber or somesuch, but as we were in a
totally different field, and as we weren't making any money from our
work, we thought that we would gladly give 50% of our earnings to the
real owners of that name, should they eventually ask for it :-)
So far we haven't had any trouble, but let's keep our fingers crossed.

Spectran was born also thanks to the availability of the excellent
Signal Processing Library from Intel Corporation, a suite of optimized
assembly language routines to perform a really rich set of signal
processing related tasks. Nothing that I have tested beats them in speed.
Just in that time frame I discovered the existence of the 137 kHz band,
and I subscribed to the RSGB reflector. There I learnt that the tool of
choice to visualize slow CW was Spectrogram, a program by R.S. Horne.
He is not a radio amateur, and he wrote that program to study the
sound of the chirping of the birds. The main drawback of Spectrogram for
QRSS work is the fact that the minimum FFT bin size is roughly 0.3 Hz,
which is adequate for 3 sec dots, but not less..
Just at that time there were on that reflector discussions about the
gain of going still slower. I suggested the use of Spectran for that,
but after some months and many feedbacks and requests for assistance,
I realized that to use it in an effective way for QRSS you had to be
familiar with some FFT concepts, like frequency resolution versus time
resolution, etc.
Also the correct choice of the waterfall speed in function of the
resolution was important.
Then I decided that I had to produce a canned version of Spectran for
QRSS work, taking out the audio processing portion, as there was nothing
to be heard in the speakers at those signal levels, but giving preset
adjustments for the more used QRSS speeds (or should I say slownesses...)
The elimination of the audio filtering and playback brought with itself
the great bonus of making the new program independent from the mixer
vagaries that in some extent plague Spectran.
There is nothing specified worse than the mixer in the Windows architecture.

Argo was born. The first versions were simpler than the current one, no
WAV saving/playback, no screen captures, only a few QRSS modes.
It took some acceptance thanks to its simplicity of use, and requests
for enhancements started to show up in the email.
I have already tried to answer to all, if some of you did write without
a response from me, please accept my apologies.
And I have implemented only a subset of what has been requested,
based on my free time and my own personal judgment of the value of the new
function requested. Thanks God there is not a committe for this.... :-)

A long story, I hope to not have bored you.

73  Alberto  I2PHD