About Using CoolEdit in HSMS

By Andrew Flowers, K0SM

Date: Mon, 22 Sep 1997 01:58:17 +0000
From: Andy. K0SM 
Organization:  K0SM 
To: hsms@tree.net
Subject: [HSMS] About using CoolEdit


For those using Cool96 for HSMS, I've found some settings that seem to
work well for me:

Settings:

First of all you have to set the correct volume of received audio into
the soundcard.  I've found a good value to be around -15dB or so on the
scale at the bottom of the screen.  This value makes it easy to see weak
pings, but loud burns still won't be clipped.  To set it, just record
some noise and play with the radio's volume control and the computer's
input sensitivity until you get the red bar to hang around -15 or so. 
It is best to record at 6khz or 8 khz.  The higher sample rates have
poor resolution at lower audio frequencies.

You can manipulate the display by going to options:settings and
selecting the 'spectral' tab.  Blackmann-harris windowing and a
logarithmic evergy plot seem to be a good match.  I use 64 bands of
resolution.  make sure the 'Reverse Color Spectrum Direction' box is
checked.
---------------------
Setting up CoolEdit on your screen:

I've found it best if you set up your screen in the following manner:
(wave forms come up in waveform view by default--select SPECTRAL VIEW
under 'view')

 1.  Open your first TX file and put it in the bottom-left of the
screen.  Drag the edges to make it as small as possible (you don't
really need to see the display).  Put this window in LOOP mode so it
will repeat endlessly when you play it.

 2.  Open another instance of CoolEdit and place it across the top of
the screen.  This will be your RX window.  This is where you will look
at the audio and copy the pings.  Make the window the length of the
screen, and the LEAST VERTICAL HEIGHT POSSIBLE.  This is very
important!  It is much easier to see the pings when all 64 of the color
bands are sqished together instead of 'chopped up' in a maximized
window.  You could use more color bands, but that slows down the
machine, and believe it or not, it can make the pings harder to decode.
When I run a sked, I keep another instance hidden behind my RX window. 
That way, if I hear a ping I can stop recording on the first window,
start recording on the second, and switch back to the first and zoom in.

 3.  I double click on the taskbar clock and syncronize it with WWV. 
That way I have a clock on screen also.
----------------------

Decoding pings:

When I hear a ping I stop recording in that window, and finish recording
in the second.  Then I go pack to the window containing the ping.  It is
possible to see the ping on the display, especially if it was long.  If
not, you can highlight the portion of the display that you think has it
(A 200ms ping usually isn't visible in a window containing 50sec of
audio, for example) and press ZOOM.  Once you have zoomed in to about 2
or three seconds, the ping should be clearly visible.  You can scrool
left or right by placing the mouse over the scale at the bottom of the
display.  The arrow will turn into a hand and you can drag left or
right.  Once you have found the ping, you can highlight it and click
zoom.  If the ping was strong enough, you should be able to read the
dots and dashes off the screen. 

If the ping was weak, you can boost the amplitude of the display by
going to OPTIONS:SETTINGS:SPECTRAL and setting the log energy plot range
to 60 or even 70 dB.  This is very helpful in getting the last letter
out of an underdense ping that is fading out.
-----------

As far as the radio is concerned, I make sure that my AGC is turned
OFF.  This way the pings will really stick out as audio peaks.


Hope to see more of you on HSCW as the winter dulldrums roll around,
Andy K0SM EN10
 Meteor Page by K0SM 


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