WriteLog
[Top] [All Lists]

[WriteLog] Sound card duplex operation?

To: <writelog@contesting.com>
Subject: [WriteLog] Sound card duplex operation?
From: "Clive Whelan" <clive.whelan@btinternet.com>
Date: Mon, 4 Jul 2005 18:54:39 -0000
List-post: <mailto:writelog@contesting.com>
Hi list

I'm not sure that the title really describes what I want to convey, please
excuse my inarticulation.

This is the problem. I am mainly - like 99%- a CW operator, but have been
known to run the occasional RTTY contest, even pick up a microphone!
Particularly noticeable has been that when running say RTTY, I get what I
would describe as feedback when transmitting canned message files -viz F
keys, despite having carefully muted all non used inputs/outputs. I had
assumed that this was a dysfunction of my soundcard, or even something in
the transceiver itself. However, quite recently I was testing an IC7400, and
also concurrently installed an external sound card ( Trust brand), but yet
the problem was exactly the same, thus eliminating both my prime suspects!
Armed with this evidence, I eventually discovered that if I muted line input
to the sound card ( the recording feed from the transceiver) then the output
from line out to the transceiver was now free of feedback. So far so good,
but this means that I cannot record audio snapshots in real time.

Now I know that others are not so afflicted, so I am really baffled as to
what the problem really is. Do the RTTY buffs have any ideas? Oh I should
have said that feedback occurs even with the line in slider at absolute
minimum, so it's not a level problem per se.

Tips appreciated.


73


Clive
GW3NJW


_______________________________________________
WriteLog mailing list
WriteLog@contesting.com
http://lists.contesting.com/mailman/listinfo/writelog
WriteLog on the web:  http://www.writelog.com/

<Prev in Thread] Current Thread [Next in Thread>