First let me say, "if it isn't a microphone it should not be connected to
the microphone input". Of course it can be done but one has to be very
careful with the method they get the soundcard level {usually between 0 dBv
and -10 dBv} down to microphone level {usually -40 dBv} and still maintain
the S/N ratio. A fixed resistive pad or attenuator with a loss of 30 dB is
the better way to go.
Now using the Line input, the control that handles the level to the line
input or accessory jack level it the correct one to use. At the same time,
it is possible to overdrive the input stage, with a the level control after
the input stage, then no amount of "turning down" the level will correct the
overdrive condition. The source {i.e. soundcard} level must be reduced.
Remember the PSK-31 signal is an analog signal designed to pass through the
analog audio path of the transmitter regardless of which input, MIC or
AUX/Line, that you choose. It is the fact that the required level of the
MIC input is some 30 to 40 dB less than that of the AUX/Line input.
73
Bob ,K4TAX
----- Original Message -----
From: <Mykeyw9@aol.com>
To: <tentec@contesting.com>
Sent: Saturday, February 02, 2008 12:38 PM
Subject: Re: [TenTec] Digital (PSK31) Communications
In a message dated 2/2/2008 9:39:27 A.M. US Mountain Standard Time,
RMcGraw@Blomand.net writes:
A comment to the point of setting vs. controlling the power on the
Jupiter.
For modes like PSK-31 the Jupiter should be configured to operate at its
rated output power or 100 watts. <SNIP>
This is basic NO NO. Reduction of the Jupiter lower to 25 or 35 watts
en have the sound card audio drive the Jupiter to 25 to 35 watts <SNIP>
Bob
Do these comments apply for both Mic input or accessory jack
Mike W9UQB/7 DM33XP
**************Biggest Grammy Award surprises of all time on AOL Music.
(http://music.aol.com/grammys/pictures/never-won-a-grammy?NCID=aolcmp003000000025
48)
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