[TenTec] Orion and PSK - overdriving computer

Mark Erbaugh mark at microenh.com
Mon Jan 19 13:37:55 EST 2004


On the Pegasus (and I presume the Jupiter), 5-pin DIN auxilliary jack line
out levels are about twice what the sound card can handle.  I seem to recall
that the ouput is about 2V P-P.  Both of these radios also have a line out
jack that is a 1.8" TRS (stereo jack, the same as on the computer line in).
The output of this jack is 1V P-P and works greate with the soundcard line
in. I don't believe that the Orion has such a jack.  If you look at the
schematic for the Pegasus, you can see two separate output circuits going to
these two outputs, so it is clear that the higher output on the DIN plug was
a deliberate design feature.

When hooking up the computer soundcard / radio interface, I prefer to use
the DIN plug since it's more convenient (you only have to make one
connection, hence just one cable).  I modified my interface (a Rascal from
K4ABT) by putting a 5K or 10K (whatever's handy) across the input so that I
can reduce the level externally to the soundcard. Another plus is that I
find it easier to adjust the level using the pot rather than messing with
the Windows soundcard mixer.  The Rascal already had a 5K  trim pot to
adjust the output level, but I rewired that to a 5K pot on the outside of
the interface. I also find that an easier way to adjust the output.


----- Original Message ----- 
From: <K4IA at aol.com>
To: <tentec at contesting.com>
Sent: Monday, January 19, 2004 1:19 PM
Subject: [TenTec] Orion and PSK - overdriving computer

> I am noticing double signals on PSK reception and it appears the Orion
> out" is seriously overdriving the computer audio soundcard.  As was
> out to me on another reflector, Windows audio controls are not effective
> eliminate this because they act too far down the circuit -- the harmonics
> already been generated.
> Unfortunately my interface has no control on that side and it appears,
> neither does the Orion.  Anyone experience similar situation and how did
you fix it?
>  I am planning to play with a resistor inline with the audio line out.
> Radio k4ia
> Craig "Buck"
> Fredericksburg, Virginia USA
> _______________________________________________
> TenTec mailing list
> TenTec at contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec

More information about the TenTec mailing list