Since the carrier null is different between LSB and USB, this would suggest
that the BFO is not properly positioned on the slope of the TX SSB filter.
The attenuation of the filter contributes to the carrier null.
A frequency counter is required to properly perform this alignment or to set
the BFO frequency. Once the BFO alignment is correct then an oscilloscope
can be used to observe the actual carrier level in the output. The
adjustment can be made and you can see that the carrier null is equal
between LSB and USB. This will likely cure the switching transit you
describe as well.
The manual covers all of these adjustments and the required equipment to
perform same.
73
Bob, K4TAX
----- Original Message -----
From: <W5OT@aol.com>
To: <tentec@contesting.com>
Sent: Wednesday, April 01, 2009 5:37 PM
Subject: [TenTec] Carrier null on Omni VI; SSB switching transient
My Omni VI has a small bit of carrier showing on LSB that is not present
on
USB. Also there is a full output switching transient when I key the mike
in
LSB; it is less than half on USB.
Can this alignment/null be performed with a minimum of test equipment? I
don't have a service monitor capable of 1 Hz readout. I seem to remember
some
discussion on the switching transient a few years ago, so I will try to
check
the archives.
73, John
**************New Low Prices on Dell Laptops – Starting at $399
(http://pr.atwola.com/promoclk/100126575x1220631247x1201390185/aol?redir=http:%2F%2Fad.doubl
eclick.net%2Fclk%3B213540506%3B35046329%3Bx)
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
|