I agree, Rodney.... the aforementioned top 20 ARE good radios.
73-
Greg, KC8HXO
<w3krq@dejazzd.com>
To: Discussion of Ten-Tec Equipment <tentec@contesting.com>
Sent: Friday, November 11, 2011 9:30 AM
Subject: Re: [TenTec] Omni VI+, VII, or Orion for next rig. Can't decide
GO ON 75/80 AT 8PM AND I TELL YOU THAT WITH 2KC SPACING YOU NEED A GOOD
RADIO
-----Original Message-----
From: Rick - DJ0IP / NJ0IP
Sent: Friday, November 11, 2011 4:48 AM
To: 'Discussion of Ten-Tec Equipment'
Subject: Re: [TenTec] Omni VI+, VII, or Orion for next rig. Can't decide
The close-in dynamic range is measured with 2kHz separation.
The SSB filters are usually 2.1 kHz, 2.4 kHz or 2.8Khz wide.
The CW filters are typically 500 Hz or 300 Hz, etc.
If your RX is centered on one of the two signals used for measuring, then
the other (disturbing) signal is just barely outside the 6dB attenuation
point of the SSB filter, but well outside the 6dB attenuation point of the
CW filter; in fact in the case of the CW filter it would be outside of the
60dB attenuation point. (Note: this assumes the Xtal filter being used is
good enough to have over 60dB of ultimate attenuation, AND that it has a
"2:1" shape factor or better, which is typical for good filters in the 9MHz
range or 5 MHz range, but difficult to nearly impossible for filters in the
60 MHz range).
As you can see, the close in measurement (2kHz separation) is a more
important figure for CW than for SSB.
73
Rick, DJ0IP
-----Original Message-----
From: tentec-bounces@contesting.com [mailto:tentec-bounces@contesting.com]
On Behalf Of Richards
Sent: Friday, November 11, 2011 2:59 AM
To: Discussion of Ten-Tec Equipment
Subject: Re: [TenTec] Omni VI+, VII, or Orion for next rig. Can't decide
Serious novice question:
Does all this close-in-third-order-intercept / up-conversion stuff
matter more to CW than to SSB ?
Seems to me it would because of the narrow bandwidth you are using with
CW. I mean, if a guy crowds you on SSB, you narrow your filters, shift
the band pass, play with the notch, and all that jazz... but on SSB you
have some room to move, some bandwidth to give up as you notch a tone
out or shift away from the offending signal overlapping your intended
range.... but on CW, you are already narrowed down and have nowhere to
go, so either the rig discriminates, or it does not, and if not, there
there is no more room to move, and... I suppose... therein lies the rub.
Does this make sense?
================================= K8JHR ============================
On 11/10/2011 12:11 PM, Rick - DJ0IP / NJ0IP wrote:
> Nice post, Floyd.
>
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