The concept of RF gain vs. S meter has always been very strange to me. If
the S meter is to indicate relative signal strength then why should the S
meter move up and down with adjustment of the RF gain control? Speaking of
ancient tube radios, and me being an AMer I have several, my Hammurland
HQ-170A does not have the S meter move up and down when the RF gain is
adjusted. The S meter always indicates relative signal strength regardless
of the RF gain adjustment. And my Paragon and Omni VI Plus does not have
the S meter move up and down when the S meter is adjusted. Of course the
signal level changes because the gain of the stages has bee reduced.
Frankly I dislike a radio that does this. If I reduce the RF gain on my
Collins 75S-3A then the S meter moves upscale as if there were signal
present. No longer is 100 uV equal to S-9. (That's Collins reference.) If
the gain of the stage(s) is reduced then the gain should go down and the S
meter should indicate the relative value of the signal for the available
signal present.
I totally agree with Martin in his last paragraph regarding how the S meter
should indicate relative signal strength.
73
Bob, K4TAX
----- Original Message -----
From: "Martin AA6E" <martin.ewing@gmail.com>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Friday, December 23, 2005 5:33 PM
Subject: Re: [TenTec] Orion with V2 rf gain
> We don't want beta testers to violate their non-disclosure agreements.
> They would have to sacrifice their first-borns, I think. (Of course,
> the O II is now visible "in the wild".)
>
> The S-meter rising with lower RF gain is an artifact of how the RF
> gain control was implemented on ancient tube-type radios. IIRC, it
> was by injecting a DC level into the AGC loop.
>
> I prefer the current (1.372) system, where the S meter stays constant.
> In my view, the S-meter should give you the best estimate of the
> actual signal level at the antenna connector. When you insert RF
> attenuation, the S meter should not change, either. An S9 signal
> should be an S9 signal, no matter how you fiddle with your controls.
>
> It's a small thing, of course. Have another glass of holiday cheer!
>
> 73 Martin AA6E
>
> On 12/23/05, Able2fly@aol.com <Able2fly@aol.com> wrote:
>>
>> _n4py@arrl.net_ (mailto:n4py@arrl.net) writes:
>>
>> Tim,
>>
>> The RF gain control on the Orion II and Orion with V2 now works like
>> other
>> radios. As you reduce RF gain, the S meter goes up and the background
>> noise
>> goes away.
>>
>> Carl Moreschi N4PY
>> >>>>>>>>>>>>>>>>>>>>>>>>>>>
>>
>>
>>
>>
>> Does that mean that Carl is an O1/V2 beta tester and knows how Orion
>> with V2
>> works? Tell us more Carl. Pleeeease.....
>>
>> ;-) Bill K3UJ
>> _______________________________________________
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>> TenTec@contesting.com
>> http://lists.contesting.com/mailman/listinfo/tentec
>>
>
>
> --
> martin.ewing@gmail.com
> http://blog.aa6e.net
> _______________________________________________
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> TenTec@contesting.com
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>
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