James and others
I don't think the s meter is at the antenna input. It's usually in the
IF circuit. TenTec worked a way to extract signal from the noise, and
measure it. If you think about it, that's not hard to do with today's
technology.
Ron
K3MIY
Quoting Richards <jruing@ameritech.net>:
> Not the same as other rigs... The Omni VII works the same as the Orion
> II, and here is what it says in the ARRL product review :
>
> The receive S-meter is worth particular
> note on two counts. First, it is the only
> S-meter I?ve encountered that provides a
> reading that just indicates receive signal
> strength.
>
> Other S-meters show wild changes in value
> with a change in preamp or attenuator setting.
> Not this radio ? its value automatically compensates
> for such changes and the readings are close
> whether the preamp is on or off or attenuation
> is inserted. Second, it showed S-9 with a 67 µV
> (only 2.5 dB, less than half an S-unit, from the
> original 50 µV standard that Collins established),
> then dropped one S-unit every 6 dB, just as
> it?s supposed to. With this radio, you can give a
> meaningful S-meter comparison between received
> signals!
>
>
> Hope this helps clarify the matter.
>
> Disclaimer - A rather non-scientific, vernacular statement follows:
>
> I understand by all of this that the S-meter reads the raw signal
> strength BEFORE the rig does stuff to it, like run the pre-amp, or
> apply the attenuator, or apply filters, so that no matter what you do to
> the signal in the rig, it reads the signal strength first, as it enters
> the rig. Thus, the signal strength is not supposed to vary if you do
> stuff to it in the rig, on its way to being converted into sound.
>
> ================ James - K8JHR =====================
>
>
>
> On 4/24/2012 10:13 AM, kc9cdt@aol.com wrote:
> > Bob,
> > I'm dense today???
> > So, if I have a nice solid S-9 signal coming in from S. Africa...and I
> > engage pre-amp, and it goes to +15 over 9....
> > Does that mean the pre-amp amplified the signal to more thanm 50uv?
> >
> > So, the s meter really is not correct as to the strength of the
> > incoming signal with ATTN or pre-amp on.
> > So we disregard the S meter with any of those guys engaged.
> >__________________________________________________
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>
>
-------------------------------------------------------------------
This mail sent through CSOnline Webmail http://webmail.csonline.net
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
|