Date:  93-10-15 10:45:34 EDT
From:  CQ-Contest-Relay@TGV.COM
Subj:  Reflections: Sound Blaster & Voice Blaster
To:    KA9FOX

                The Sound Blaster Card & Voice Blaster Software
                    Reflections by Walt Kornienko - K2WK
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     I recently acquired a Sound Blaster Pro card for my PC. The purpose
of which was to have the ability to "play" Tack's PED program and double
as a digital voice keyer. Not to mention all the other neat things I
discovered the SB card can do in totally awesome stereo.
     I also purchased the "Voice Blaster" software. This is a TSR that allows
you to play/record up to 8 messages, accessible through function keys F1-F8.
Recording is accomplished by "shifting" the function keys. Much like CT in CW.
     The program allows you to load the messages in XMS (above 1Meg) memory.
The amount of data that can be recorded or loaded is only limited by the 
available memory on the PC. My machine is a 386/33 with 4Megs of RAM.
The program has the ability to load more than 8 messages by exiting the 
program and loading another set of up to 8 messages by using the "log" feature.
This feature was probably developed for multi set-ups, but is also useful for 
the single op.  Its possible to have separate banks of messages for various 
activities. For instance, I use a logging program and have a set of messages 
setup for general DXing (my call, my call twice, CQ, QRZ, etc.). I can also 
set up a bank of messages for contesting. One bank for World Wide another for 
SS, and so on.
     The program comes with a schematic of an interface box that can be built
to go between the PC and your rig.  It essentially, provides for PTT via a COM 
or LPT port and some isolation between the sound board and the rig.  This is
accomplished via an isolation transformer and relays. My circuit differs in 
that I interfaced the sound card to my rig, mike and stereo via a 4 channel 
mike mixer. Proper shielding of all leads, cables and power supply is
ESSENTIAL for RFI-proof operation. Use an external power supply if at all
possible.  I first tried powering the interface from 13.8VDC available at the
back of my Icom 765, which failed miserably. Even at 100W power levels the RF
feedback was horrendous.  I connected the unit to a well regulated outboard
power supply and have had no problems with RF feed back on all bands running 
1500W.  Proper station grounding is essential to maintaining a clean signal.
     It appears that VB records at 8 khz and the quality of the recording 
suffers.  I have gotten around this by prerecording my messages using various 
Windows & DOS-based Sound Blaster utilities.  The quality is superb and sounds 
quite professional over the air.  I make my off-the-air recordings using 
Window's Sound Recorder utility, at 22kHZ. The recordings are truly hi-fi.
     Some caveats:  
     If you use a memory hogging logging program and load VB and messages in 
conventional memory you won't have much room to hold more than your call-sign.
Using 1024K of XMS memory is advisable.  Got more? Use it!
     I wired my VB (PTT) control via LPT2, as this is the port through which
I key CT on CW.  When the PC is rebooting evidently Pin 2 (or 3?) goes high and
puts the rig into transmit. I wait a few seconds before turning on the rig.
     I tried to get the program to work in Windoze. Well, I can load the TSR 
and messages ONLY in conventional memory. I then load my logging program. After
several hours of being connected to the cluster the system seems to hang for
unknown reasons.  I tried loading the messages into XMS memory (via pif files) 
but it didn't work.
     Well, I hope this answers some of your questions as to what "Voice Blaster"
is and what it does. Naturally, I have no connection to any of the 
manufacturers.
                              73,   de Walt - K2WK


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