[RTTY] Omni-V and FSK

[Keith Regli]

I agree with everything John said in his post.  One thing he did leave
out that may still be confusing is the interconnect scheme.  

For AFSK it is pretty simple - run an audio cable from one side of the
soundcard output (it's stereo) to your mic jack (it's mono).  You can
use an isolation transformer to avoid ground loops if you choose.

For FSK you have to choose if you want your program to output on an LPT
port or a COM port.  On Windows NT, 2000 and XP you need a driver if you
choose the LPT port.  In either case you need to isolate the computer
output from the Omni (and match the levels).

There are dozens of sites with circuit descriptions as well as vendors
who sell cables with the appropriate stuff built in.  See
http://www.aa5au.com/rtty and http://www.rttyinfo.net/ as well as the
archives on this reflector to get started.

If the OMNI V is like the OMNI VI+ it keys FSK "upside down" using the
normal circuits and you have to make an adjustment.  I can send you a
simple circuit to do that for the serial port.

Keith Regli (K7KAR)
mailto:keith at kregli.com
http://www.kregli.com 

>
> Just picked up an Omni-V and need some advice for setting up FSK. If I

> use MMTTY it still needs the soundcard for RX. I  set the default 
> encoding to "Ham" that uses the default normal ham settings for shift 
> and mark/space.
So
> what are the advantages to change to true FSK ??  I can use a PK 232 
> but lack a good terminal program for it. Just a newbie that is a 
> little confused. TIA.....73
>
> Ed W3NR