[CQ-Contest] SO2R and broadband noise

[Dick Frey - K4XU]

Pete,
This is the phase noise of the 930's LO, plus the amplified noise figure of the transmitter stages all the way back to the carrier generator. Because it goes out through the Tx LPF you will find it more on frequencies below the band it's on.
73, Dick

Message: 5
Date: Fri, 06 Jan 2006 14:13:50 -0500
From: Pete Smith <n4zr at contesting.com>
Subject: [CQ-Contest] SO2R and broadband noise
To: cq-contest at contesting.com
Message-ID: <6.2.0.14.2.20060106140800.0c730150 at mail.adelphia.net>
Content-Type: text/plain; charset="us-ascii"

I have been doing some tests with my new single-tower SO2R setup, transmitting on a TS-930S and listening on a Mark 5.
Results so far are very gratifying.  I have noticed, though, that regardless of band, when I have the TS-930 in transmit, but not key-down, I can hear a slight increase in the noise floor on the Mark 5.  The amount of increase is subjectively the same, whatever band I'm listening on, and does *not* change between key up and key down.

I'd characterize this as a nuisance, and probably not an operational problem under extreme weak-signal conditions, but I'm curious what could be causing it.  Any thoughts?  

73, Pete N4ZR
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