[CQ-Contest] RF Problem with Array Solutions SO2R box

[Mark Bailey]

Hi Ronald:

I've done some more research.  I'm using TR-Log.  Jay
from Array Solutions provided a suggestion for filtering RF
noise.

The problem appears to be that the LPT port in this computer
can't drive the STROBE, PTT, CW, Radio A/B and one
paddle (DIT or DAH) reliably in the presence of RF.

I can see the PTT voltage levels varying a little bit on a
voltmeter, following the paddle keying.  This is enough to
cause the PTT sensing in the audio switching to follow the
keying.

The radio A/B select is so marginal that adding a voltmeter
probe to one specific leg of the input circuit causes something
to go into oscillation!

I'm going to try a different computer, with a different LPT
port type.  I suppose I should build an opto-isolated interface...

Thanks and 73,

Mark, KD4D



----- Original Message -----
From: "Ronald Rossi" <rrossi at btv.ibm.com>
To: "Mark Bailey" <mark at ilexeng.com>
Sent: Tuesday, August 06, 2002 12:02 AM
Subject: Re: [CQ-Contest] RF Problem with Array Solutions SO2R box


> What are the paddles hooked up too? Do they drive a keyer feeding the
> box? Are they feeding the LPT port and the computer is generating the CW
> and PTT? Could it be the PTT generation is not right? What software are
> you using?
>
> Mark Bailey wrote:
> >
> > Hello, All:
> >
> > I am in PJ2 with an Array Solutions SO2R Master.  I'm having
> > intermittent RF problems.  They appear to be with the receive
> > audio switching relay...it's chattering or switching when the paddle
> > sends CW.  The radio is a TS940.  I haven't hooked up the
> > second radio yet!
> >
> > Has anyone had similar problems?  Any suggestions?
> >
> > I have grounded the SO2R box and computer, added ferrites
> > on the power and computer (LPT) cables and swapped the
> > "wall wort" power supply.  I'm about to poke around with
> > bypass capacitors.
> >
> > Thanks in advance.
> >
> > 73,
> >
> > Mark, KD4D
> > kd4d at comcast.net
> >
> > _______________________________________________
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> > CQ-Contest at contesting.com
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>
> --
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> QTH: Jericho, Vermont
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